The Pacific coastal Peruvian landscapes are dominated by desert and dry-forest biomes, which have undergone shifts in extent and floral composition in response to Plio–Pleistocene climatic fluctuations. Within this context, the coastal Lomas develop as seasonal vegetation patches, renowned for their high endemism, rich floral diversity, and essential ecosystem services. Despite growing within the desert biome, the Lomas exhibit characteristic elements and vegetation structure typical of a dry-forest biome, evidencing an active species migration between xeric biomes. However, assessing the historical evolution of this arid flora and, by extension, the coastal desert landscape, presents challenges. The scarcity of continental sedimentary records and a lack of extended and well-described palynological references impede these efforts. In response to this, our study offers a thorough morphological review of the Lomas palynoflora, encompassing over 194 genera from 76 families, representing approximately 80% of the known Lomas flora. Our review includes at least one species per reviewed genus, featuring 37 palynomorphs from endemic species (18.5% of the studied flora). This palynological characterization is intended to serve as accessible reference material for investigating the historical and long-term evolution of the coastal dry flora. Furthermore, these findings facilitate the analysis of honeys and bee floral foraging patterns, as well as the study of animal–plant or human–plant interactions from middens and archaeological remains.

Along the western coast of South America spans a continuous (hyper)arid belt stretching 3500 km from northern Peru to Chile (6–30°S; Dillon 1997; Dillon et al. 2003; Houston 2006), encompassing both the Atacama Desert and the Peruvian Desert. In the central Peruvian region (8–16°S), these hyper-arid settings receive a mean annual precipitation (MAP) ranging from 0 to 10 mm and experience average annual temperatures of approximately 18–20 °C (Rundel et al. 1991; Tovar et al. 2018). The climatic regime is characterized by a constant temperature inversion generated by the Humboldt Current and the seasonal position of the South Pacific anticyclone, resulting in a seasonal coastal climate. During the austral summer months (DJF), fog-humidity originates in the early morning and rises as air masses warm, forming light showers locally called ‘garúa’. In contrast, during the austral winter months (JJA), thick stratus cloud banks form below 1000 meters above sea level (masl), creating a fog zone that increases local moisture availability and serves as an important source of humidity for these hyper-arid biomes (Dillon 1989; Dillon and Rundel 1990; Galán de Mera et al. 2011; Trujillo and Rodríguez 2011; Reynel et al. 2013). Experimental studies on fog-derived water collection in lowland Peruvian settings indicate average water accumulation of up to 224 mm/year (ranging from 4.7 to 785.3 mm/year; Gonzales et al. 2023). This seasonal fog-driven moisture fosters the development of isolated but diverse vegetation patches known as Lomas (Weberbauer 1945; Rundel et al. 1991; Rundel and Dillon 1998; Dillon et al. 2003; Pinto et al. 2006), which typically grow from 400 to 1000 masl.

Although the climatic conditions of the Lomas ecosystem are primarily influenced by the northward-flowing cold waters of the Humboldt Current, changes in precipitation patterns and the availability of fog-derived moisture during both extreme phases of the El Niño Southern Oscillation (ENSO) cycle (i.e. warm and wet phase during El Niño and cold and dry phase during La Niña) also impact the greening of the Lomas (e.g. Dillon and Rundel 1990; Manrique et al. 2010; Eichler and Londoño 2013). These changes are known to alter the regular reproduction and seedling cycles, thereby promoting vegetation expansion and persistence, as well as affecting food web dynamics (Ferreyra 1957, 1993; Oka and Ogawa 1984; Vincenti 2004; Eichler and Londoño 2013; Santa Cruz et al. 2020; Gonzales et al. 2023).

The Lomas formations are characterized by the seasonal growth of diverse flora, containing abundant endemic flora. Lomas vegetation is highly dynamic, with some species remaining consistent every year while others fluctuate, appearing and disappearing with the seasons (Dillon et al. 2011). Some studies suggest that up to 30% of the Peruvian coastal plant species are found exclusively within this biome (Ferreyra 1957, 1961, 1983, 1993; Rundel et al. 1991; León et al. 1997; Cano et al. 1999). Their vegetation comprises ca. 1200 species of tracheophytes (including pteridophytes and spermatophytes), classified into 83 families and 347 genera. The majority of the vegetation corresponds to herbs (80%), with species such as Nolana humifusa, Ismene amancaes, and Begonia octapetala. However, a few arborescent species (e.g. Schinus molle, Myrcianthes ferreyrae, Sapindus saponaria), seasonal shrubs (e.g. Heliotropium arborescens, Tournefortia schomburgkii, Croton alinfolius), cacti (e.g. Neoraimondia arequipensis, Echinopsis chalaensis), and epiphytic ferns (e.g. Hemionitis nivea, Blechnum occidentale, Ophioglossum crotalophoroides) can also be found (Weberbauer 1945; Cano et al. 1999; León et al. 2002; Dillon et al. 2011; Schulz et al. 2011; Stotz et al. 2021).

Modern Lomas vegetation, although part of the coastal desert, is compositionally closely linked to the Peruvian dry forest biome (Whaley et al. 2019), particularly to the flora of the seasonal dry forests of the northern and central Peruvian coasts (Linares-Palomino et al. 2022). This vegetation shares the distribution of ecologically important native trees, such as Caesalpinia spinosa, two species of Neltuma (ex-Prosopis), and Carica candicans (Dillon et al. 2011). Despite these floristic similarities, the origin, extent, and ecological evolution of the Lomas vegetation remain uncertain. It is unclear whether these vegetation communities result exclusively from long-term adaptations to aridity and/or CO2 changes, or correspond to relict vegetation from the lowland dry forests (e.g. López et al. 2006; Gonzales et al. 2023). Some authors suggest that its origin is related to an Andean uplift pulse during the Pliocene (4–3 Ma; Hartley and Chong 2002; Hartley 2003), whereas others propose that it may have arisen during the late Miocene (8 Ma; Gonzales et al. 2023). Regardless of its origin, the Lomas formations play a critical role as habitats and corridors for several wild species, such as guanacos, desert foxes, and condors (Moat et al. 2021).

These unique ecosystems have also been fundamental in shaping South American human history and coastal settlements from the Middle Preceramic period (ca. 8000–4500 BP) to the present (e.g. Beresford-Jones et al. 2015; Moat et al. 2021). They provide shelter, essential resources for sustenance (potato, pumpkin, papaya), abundant fuel material, and venues for a variety of human activities (Engel 1973; Rundel et al. 1991; Beresford-Jones et al. 2015; Marcone et al. 2024). As a result, historical and modern anthropogenic activities have exerted continuous pressure on the Lomas ecosystem. Overgrazing and constant extraction of resources, especially wood, have affected the natural balance of this ecosystem, putting its diversity at risk (Arana and Salinas 2005; Nieuwland and Mamani 2017). In more recent times, continuous and accelerated unplanned urban expansion is decreasing their natural extension, posing an additional threat to these fragile vegetation patches (Dall’Orso and Román 2019; Alonso and Solórzano 2021).

Despite its ecological importance, the palynological characteristics of the Peruvian coastal Lomas flora remain unexplored (Engel 1973). Existing works addressing the palynological spectrum of the Peruvian xeric flora either have focused on specific taxonomic groups or are limited to the most common species (Schneider et al. 2009; Douglas and Freyre 2010; Finot et al. 2018). The present study aims to fill this knowledge gap by presenting a comprehensive and taxonomically updated palynological record encompassing over 194 genera from 76 families, including 37 endemic species, from two of the most diverse Peruvian Lomas (Lachay and Atiquipa; Figure 1). This review will serve as a primary reference for future (paleo)palynological studies, particularly those focused on dry environments and the evolution of flora in the western Andes. Future efforts will be focused on completing the characterization of the Lomas palynoflora at the genus level by describing the remaining 153 genera.

Study area and sample origin

Our study area encompasses flora from two of the largest and most diverse Lomas across the Peruvian coasts (Figure 1): Lachay (11°20′48″S, 77°19′45″W) and Atiquipa (15°45′35″S, 74°21′34″W). The former has an extension of 5070 ha and an altitude of 350 masl; it hosts 146 plant species, grouped in 124 genera and 52 families. The latter has an extension of 19,028.02 ha and rises to an elevation of 800 masl, accommodating 350 species grouped in 236 genera and 78 families (Dillon 1997; Cano et al. 1999; León et al. 2002; Talavera et al. 2017; Moat et al. 2021; Gonzales et al. 2023). We collected over 251 vegetative samples ex situ from the herbarium at the National History Museum of the Universidad Nacional Mayor de San Marcos (MHN-UNMSM), following standard protocols for pollen grain and spore extraction (Jarzen and Jarzen 2006). Only georeferenced material was sampled, and all botanical names were updated using the Rpackage taxize (Chamberlain and Boettiger 2017). The last botanical name update was carried out on 1 May 2024. Appendix 1 (Supplementary material) contains a comprehensive inventory of sampled specimens, including information on herbarium vouchers and whether they produced positive or negative palynological results.

Sample preparation and housing

We followed a modified four-step palynological protocol proposed by Riding (2021) for sporomorph sample preparation. First, we collected and cleansed samples, removing any excess organic material and placing the anthers in a 2 mL Eppendorf tube. Second, we subjected the samples to an oxidative process with a 50% KOH solution (1.5 mL) at 100 °C for 2 h to eliminate any residual organic material. Third, we stopped the KOH reaction by centrifuging the samples for 5 min at 2500 rpm, followed by decanting and adding distilled water three times. Finally, we dehydrated the samples by adding five drops of xylene and mounted them using Canada balsam as a medium. The slides were then dried at 50 °C for 24 h.

The samples are housed at the Biogeosciences Laboratory of the Universidad Peruana Cayetano Heredia (UPCH), where they will constitute a palynological reference collection of the Peruvian Lomas. A replica of all samples will also be available for public access at the Herbario Sur Peruano (HSP) of the Instituto Científico Michael Owen Dillon (IMOD) in Arequipa, the region where the most diverse Lomas (Atiquipa) is located.

Palynomorph characterization: imaging, description, and morphometric measurements

Pollen and spores were described and photographed using a Nikon Eclipse Ci microscope and a TOUPCAM E3ISPM camera at 40× and 100× magnification. We attempted to capture images in polar and equatorial views for pollen grains and proximal and distal views for spores. To ensure consistent terminology in our descriptions, we used Punt et al. (2007) as our primary glossary reference. Palynomorph sizes were classified according to Erdtman (1952). Morphometric information complementing our descriptions was obtained by taking measurements of at least 20 individuals (n = 20) per taxon (Supplementary material, Appendix 2). These measurements included taxonomic characters such as the length and width ranges of palynomorphs, aperture length, wall thickness (exine or sclerine), and sculptural elements among others. Some of these characters were measured using the ToupView software for more exactitude on the smallest structures. Additionally, we followed descriptive parameters from Heusser (1971), Silva-Caminha et al. (2010) and Fontes et al. (2020), who compared morphological characteristics with related taxa. Appendix 3 (Supplementary material) contains a summary table detailing key morphological features. High-resolution photographs of any specimen are available upon request. High-resolution plates can be accessed at: http://hdl.handle.net/10366/159563.

This catalog describes 202 palynomorph types belonging to 200 species, 194 genera and 76 families. Typically, each genus corresponds to at least one palynomorph. However, exceptions include Melochia and Waltheria within the Malvaceae family, which are heterostylous species, each having two pollen types. Species are alphabetically organized according to family and genus names, starting with gymnosperms (n = 1 species), followed by angiosperms (n = 180 species), and concluding with pteridophytes (n = 19 species). Palynological descriptions are presented in the following order: species name, unit, symmetry, polarity, shape and amb, palynomorph size, exine or sporoderm details, and aperture details, concluding with notable key morphological remarks. We have added an indication next to the names of endemic species and when describing the palynological features of a species for the first time (n = 114; Supplementary material, Appendix 1), to the best of our knowledge. In addition to the positively recovered and described palynomorphs, 51 additional herbarium specimens yielded negative results (Supplementary material, Appendix 1). Appendix 3 (Supplementary material) contains a summary table detailing key morphological features per specimen, which serve as a search index by morphology.

Palynological descriptions

GYMNOSPERMS

EPHEDRACEAE Dumort.

Species.Ephedra americana Humb. & Bonpl. ex Willd. (Plate 1, figures 1–5)

Description. Monad, bilaterally symmetrical, apolar, circular amb, ellipsoidal outline in equatorial view, prolate shape. Medium size (25–35 µm). Eutectate exine 1 to 1.3 µm thick. Slightly visible nexine. Tectum 0.5 to 0.7 µm thick. Inconspicuous columellae. Plicate, 10 to 12 plicae extending from pole to pole, and 5 to 6 µm wide. Plicae’s surface is psilate. Inaperturate.

Remarks. Ellipsoidal outline. Inaperturate. There are weak exine zones between plicae, almost looking like ‘pseudo-colpi’.

ANGIOSPERMS

ACANTHACEAE Juss.

Species.Dicliptera tomentosa (Vahl) Nees. (ex-Dicliptera ruiziana) (Plate 1, figures 6–10)

–Endemic species for Peru–

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate to perprolate shape. Medium to large size (35–56 µm). The exine is semitectate, about 3 µm thick, with conspicuous columella ranging from <1 to 1.5 µm, tectum about 1 µm. The ornamentation is reticulate heterobrochate, with lumina decreasing in size toward the apocolpium. Muri decrease in thickness in the same direction. Tricolporate. Simple ectocolpi about 35 to 50 µm long and 7 to 12 µm wide, reaching the apocolpium zone, with rounded ends. Circular to slightly lalongate endopores, about 5 to 10 µm wide. Parallel to colpori, there are weakened exine zones (‘pseudocolpi’) on each side of the aperture. Pseudocolpi are as long as colpori but narrower, 2 to 3 µm wide.

Remarks. Elliptical outline. Medium to large size. Reticulate, heterobrochate. Tricolporate with one pseudocolpus each side the aperture. This is the only morphotype within the Lomas flora that is reticulate and has two pseudocolpus features along each aperture.

Species.Dyschoriste repens (Nees) Kuntze (Plate 1, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate shape. Medium to large size (45–57 µm). Exine is tectate perforate, about 2 to 2.2 µm thick. Slightly visible nexine (0.5 µm). Tectum is 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm high. Punctate. Lumina 0.5 µm wide or less. Tricolporate. Simple ectocolpi about 30 to 45 µm long and 3 to 4 µm wide, reaching the apocolpium zone, with acute ends. Circular endopores, 4 to 5 µm in diameter. At the mesocolpium, there are 5 to 6 ‘pseudocolpi’ parallel to the apertures, giving the grain an appearance of having plicae or being heterocolpate. Pseudocolpi are about 1 µm wide.

Remarks. Elliptical truncate outline. Medium to large size. Punctate. Tricolporate with pseudocolpi (5–6) in between. Number of pseudocolpi between apertures (5–6), in conjunction with the punctate ornamentation, is a diagnostic characteristic for this genus (within the Lomas flora).

AIZOACEAE Martinov

Species.Sesuvium portulacastrum (L.) L. (Plate 1, figures 16–20)

Description. Monad, radially symmetrical, isopolar, circular amb, prolate shape. Small to medium size (20–30 µm). Semitectate exine, about 1 to 1.2 µm thick. Tectum 0.5 µm, columellae conspicuous, about 0.5 µm high. Punctate. Puncta range from 0.5 to 0.8 µm wide, fusing at the apocolpium zone, where wider lumina are found. Smaller lumina occur in the mesocolpium zone. Tricolpate. Simple colpi and pontoperculate, reaching the apocolpium zone; its length ranges from 17 to 28 µm, and its width, 5 to 8 µm. Colpi with irregular margins. The pontoperculum is ornamented (punctate) but is not always preserved.

Remarks. Small to medium size. Punctate, wider puncta at the apocolpium zone and narrow toward the aperture. Tricolpate. Pontoperculate.

Species.Tetragonia crystallina L'Hér. (Plate 1, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, spheroidal shape. Medium size (28–33 µm). Semitectate exine, 2 to 2.2 µm thick. Slightly visible nexine (0.5 µm). Tectum is 0.5 to 0.7 µm thick, columellae conspicuous, 0.8 to 1 µm high. Foveolate. Foveolae of variable width, about 0.7 to 2 µm wide, spread uniformly across the surface. Tricolpate. Colpi are marginate, about 18 to 22 µm long and 3 to 5 µm wide.

Remarks. Medium size. Foveolate. Lumina of variable size widespread across the whole surface. Tricolpate.

ALSTROEMERIACEAE Dumort.

Species.Alstroemeria paupercula Phil. (ex-Alstroemeria violacea) (Plate 1, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Large size (60–95 µm). Eutectate exine, thickening slightly toward the equator, about 2 to 2.3 µm thick. Visible nexine 0.5 µm thick. Tectum about 0.5 to 0.7 µm thick. Conspicuous columellae 1 µm high. Striate. Striae concentrically arranged from the equator to poles. Monosulcate. Sulcus is marginate, as large as the grain itself, ranging from 50 to 90 µm long and 3 to 5 µm wide. Sulcus with irregular margins and rounded end.

Remarks. Large size. Heteropolar, ellipsoidal amb, reniform shape. Thick exine. Monocotyledonous pollen grain with striate ornamentation unique within the analyzed Lomas flora. Large grain. Striae form unusual and irregular projections.

Species.Bomarea ovata (Cav.) Mirb. (Plate 1, figures 31–35)

–Endemic species for the Atiquipa Lomas

Description. Monad, bilaterally symmetrical, ellipsoidal amb, reniform shape. Medium to large size (40–70 µm). Semitectate exine is about 2 µm thick. Visible nexine about 0.5 µm thick. Tectum is about 0.5 µm thick. Conspicuous columellae are about 1 µm high. Exine becomes thicker toward the equator. Reticulate heterobrochate, lumina with irregular shapes, ranging from 1 to 2 µm wide, with muri 0.5 to 0.7 µm wide. Lumina become narrower toward the aperture and the poles. Monosulcate. Slightly marginate sulcus with irregular borders, passing to the distal face (longicolpate). Sulcus ranges from 38 to 60 µm long and is 4 µm wide.

Remarks. Wider lumina and thicker exine toward the equator. Sulcus reaching distal face (longicolpate) in length.

AMARANTHACEAE Juss.

Species.Alternanthera halimifolia (Lam.) Standl. ex Pittier (Plate 1, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Small grain (10–15 µm). Semitectate exine about 2 µm thick. Tectum 1 µm thick, conspicuous columella ranging from 0.5 to 0.8 µm high. Lophate, metareticulate (each aperture is enclosed by the lumen’s murus). Lumen shape pentagonal to hexagonal, 4 to 5 µm in width. Simplecolumellate muri 1 µm wide, with compactly arranged columellae. Pantoporate (20–25 pores), with one small circular pore per lumina. Pores almost fill the lumina space, and are 3.5 to 4 µm in diameter.

Remarks. Small size. Lophate. The relation between each lacuna and the apertures resembles a metareticulate condition. However, the murus of the lophae is more compact and homogeneous in shape than in the case of Kallstroemia and Tribulus (see family Zygophyllaceae). Pantoporate (20–25 pores).

Species.Amaranthus spinosus L. (Plate 2, figures 1–5)

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Small size (10–15 µm). Eutectate exine 1 to 1.2 µm thick. Nexine not visible. Tectum 0.5 to 0.7 µm thick, inconspicuous columellae less than 0.5 µm high. Exine is slightly depressed around the aperture. Psilate – scabrate. Pantoporate (40–50 pores). Costate circular pores 2 to 3 µm in diameter. Costa is about 0.7 µm thick. Pores separated by 2 to 3 µm.

Remarks. Small size. Psilate to scabrate. Exine contour has an ‘undulated’ appearance, given the depression of the exine toward the aperture. Pantoporate (40–50 pores).

Species.Atriplex imbricata (Moq.) D. Dietr. (Plate 2, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Small size (15–20 µm). Semitectate exine 1.8 to 2 µm thick. Slightly visible nexine 0.5 µm. Tectum 1.5 µm thick and conspicuous columellae ranging from 0.8 to 1 µm high. Foveolate. Circular foveolae about 0.7 to 1 µm wide, densely dispersed across the surface. Pantoporate (25 pores). Costate circular pores, about 3 µm in diameter. Costa is 1 µm thick. Pores separated by 3 to 5 µm.

Remarks. Small size. Tectum and costa are thicker than in the case of Amaranthus, visible columellae. Atriplex has fewer pores and greater distances between apertures. Pantoporate (25 pores).

Species.Chenopodium petiolare Kunth (Plate 2, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Small size (18–20 µm). Eutectate exine, 2 µm thick. Slightly visible nexine 0.3 to 0.5 µm thick. Tectum 0.5 to 0.7 µm thick, inconspicuous columellae 1 µm high. Psilate to slightly scabrate. Pantoporate (30 pores). Simple circular pores 2 µm in diameter. Each pore connects to others by a very thin ‘path’, resulting from a weakening of the exine thickness. This connection opens the possibility of having a perisyncolporate condition, rather than a pantoporate one.

Remarks. Small size. Simple pores. Presence of a ‘connecting path’ between apertures. Likely having a perisyncolporate condition.

Species.Gomphrena meyeniana Walp. (Plate 2, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Medium size (28–40 µm). Semitectate exine, about 3 to 4 µm thick. Visible nexine 0.5 µm. Tectum 0.5 µm, very conspicuous columellae 1.5 to 2.5 µm height. Lophate, metareticulate. Lophae are 4 to 6 µm wide, with a pentagonal to hexagonal shape. Some grains that experience turgidity may display lophae of irregular shapes. Simplicolumellate muri are 1.2 µm wide. Pantoporate (20–25 pores). Inconspicuous circular pores 4 to 5 µm in diameter, having almost the same size as the lumina.

Remarks. Medium size. Lophate, metareticulate. In contrast to Alternanthera, this grain is larger, and exine has a less compacted appearance.

Species.Guilleminea densa (Willd. ex Schult.) Moq. (Plate 2, figures 21–25)

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Small size (15–20 µm). Semitectate exine 1.8 to 2 µm thick. Visible nexine 0.3 to 0.5 µm. Tectum is 0.5 µm thick. Columellae range from 0.5 to 0.7 µm high. Lophate and metareticulate. Lophae are 3 µm wide, with variable shapes varying from circular to hexagonal. Simplicolumellate muri, with a compact appearance about 1 µm thick. Pantoporate (50 pores). Simple, small circular pores, ranging from 1 to 1.5 µm in diameter. Pores are inconspicuous.

Remarks. Small size. Lophate, metareticulate. In contrast to Alternanthera and Gomphrena, this pollen grain has more lacunae, smaller muri and a higher number of pores.

AMARYLLIDACEAE J.St.-Hil.

Species.Clinanthus incarum (Kraenzl.) Meerow (Plate 2, figures 26–30)

–Endemic species for Peru–

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Large size (50–75 µm). Semitectate exine, about 1.5 µm thick. Exine thickness increases toward the distal face of the grain, due to an increase of columellae. Tectum 0.5 to 0.7 µm high, conspicuous columellae 1 to 1.2 µm high. Reticulate, heterobrochate. Lumina are 0.5 to 5 µm wide, with irregular shapes and decreasing in size toward the axes of the grain, turning into small puncta about 0.5 µm wide. Change in lumen size is sharp, and occurs close to the margin. Simplicolumellate muri are about 0.7 µm wide. Monosulcate. Simple sulcus, about 45 to 65 µm long and 3 to 5 µm wide. Not found in polar view.

Remarks. Large size. Ellipsoidal amb, reniform shape. Reticulate, heterobrochate. Simplicolumellate. Morphotype similar to Bomarea (Alstroemeriaceae) but differing in exine thickness and lumen/murus ratio. Clinanthus has wider lumina.

Species.Ismene amancaes (Ruiz & Pav.) Herb. (Plate 2, figures 31–35)

–Endemic species for Peru–

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Very large size (110–125 µm). Semitectate exine 5 to 6 µm, losing thickness toward the axes of the grain, reaching 1 µm in thickness at that point. Conspicuous nexine at the lateral axes. Tectum ranges from 1 µm at the axes to 3 to 3.5 µm thick at the central part of the grain. Conspicuous columellae, varying in shape and size from baculae 1 µm high to clavae 2 µm high. Reticulate, with free-standing columella looking like a bacula 2 µm high. Simplicolumellate muri 2 µm thick and very irregular in shape. The lumina are about 1 to 5 µm in width with very irregular shapes. Ornamentation changes are abrupt, occurring close to margins. Monosulcate. Inconspicuous sulcus, ranging from 75 to 90 µm in length and about 5 to 7 µm wide.

Remarks. Very large size. Reticulate, heterobrochate. Lumina decreasing toward the lateral axes of the grain, leaving only free-standing columellae or bacula-like structures, which become thinner toward the poles.

Species.Allium neapolitanum Cirillo (ex-Nothoscordum inodorum) (Plate 2, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (32–40 µm). Semitectate exine, homogeneously thick, about 1 to 1.2 µm thick. Slightly visible nexine 0.5 µm. Tectum is 0.5 µm thick and the conspicuous columellae are 0.5 to 0.7 µm high. Reticulate (slightly heterobrochate). Lumina are about 0.5 to 1 µm wide, sometimes decreasing in size toward the aperture. Simplecolumellate muri, 0.5 µm thick or even thinner. Monosulcate. Simple irregular sulcus, 28 to 37 µm long and about 6 to 8 µm wide.

Remarks. Large size. Reticulate (slightly heterobrochate). Among the reticulate monocotyledonous pollen grains, Nothoscordum has the smoother reticula shape and the smallest lumen/murus ratio.

Species.Pyrolirion tubiflorum (L'Hér.) M.Roem. (Plate 3, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Large size (70–80 µm). Semitectate exine, about 2 µm thick. Very thin nexine. Tectum is 1 to 1.2 µm thick. Columella are about 1 to 1.3 µm high. Reticulate and slightly heterobrochate. Lumina of irregular shapes, wider at the equator (4 to 5 µm) and decreasing in size close to the axis (about 2 µm wide). Simplecolumellate muri, about 1 µm thick. Monosulcate. Marginate sulcus 62 to 70 µm long and 5 µm wide. Not found in polar view.

Remarks. Large size. Heteropolar, ellipsoidal amb, reniform shape. Reticulate, (slightly) heterobrochate. Lumina with irregular shapes. Lumen size does not decrease as much as in Clinanthus.

Species.Stenomesson miniatum (Herb.) Ravenna (Plate 3, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Large size (60–65 µm). Semitectate exine 1 to 1.5 µm thick, thickening slightly toward the axis. Slightly visible thin nexine (0.2 µm). Tectum is 0.5 µm thick, conspicuous columellae 0.8 to 1 µm high, decreasing in size toward the axes. Reticulate heterobrochate. Lumina width is about 3 to 4 µm in the central part of the grain, and becomes considerably smaller toward the axis, approximately 1 µm. Lumina with irregular shapes. Simplicolumellate thin muri 0.5 µm wide. Monosulcate. Marginate sulcus 50 to 62 µm long and 2 to 3 µm wide, exceeding the proximal face of the grain, with acute ends.

Remarks. Large size. Heteropolar, ellipsoidal amb, reniform shape. Reticulate heterobrochate. Lumina become considerably smaller toward the axis. Morphology similar to Clinanthus (Amaryllidaceae).

ANACARDIACEAE R.Br.

Species.Schinus molle L. (Plate 3, figures 11–15)

Description. Monad, radially symmetrical, isopolar, subtriangular amb, oblate spheroidal shape. Small to medium size (20–25 µm). Eutectate exine, about 1 to 1.5 µm thick. Visible nexine. Tectum is 0.5 µm thick. Visible but indistinct columellae 0.8 to 1 µm high. Striato-reticulate, striae are 0.3 to 0.5 µm thick, running from pole to pole, and forming small lumina about 0.3 to 0.8 µm wide. Tricolporate. Marginate ectocolpi, reaching the poles (18 to 20 µm long and 3 to 4 µm wide), with rounded ends. Ectocolpi have a characteristic exine thickening at the apocolpium zone. Lalongate endoapertures, costate, 7 to 10 µm wide and 3 µm high. Exine separates toward the endoaperture, forming a fastigium about 0.7 to 1 µm high, which in polar view gives the grain an internal circular shadow.

Remarks. Small size. Exine thickening in polar view. Striato-reticulate. Ectocolpi with a thickening at the apocolpium zone. Tricolporate. Fastigiate.

APIACEAE Lindl.

Species.Daucus montanus Humb. & Bonpl. ex Schult. (Plate 3, figures 16–20)

Description. Monad, radially symmetrical, isopolar, prolate shape. Medium size (25–35 µm). Tectate perforate exine, about 1.5 to 2 µm thick. Visible nexine (1 µm). Tectum about 0.3 to 0.5 µm thick. Conspicuous columellae 0.5 µm high. Punctate. Circular puncta 0.3 to 0.6 µm in diameter. Tricolporate. Marginate brevicolpi are 17 to 22 µm long and 2 µm wide, not reaching the apocolpium zone, with acute ends. Costate lalongate endopores, about 3 µm high, 5 to 6.5 µm wide. Endocosta gives the grain an ‘ear-like’ appearance in equatorial view. Not found in polar view.

Remarks. Medium size. Aperture morphology: brevicolpate and endocostate ear-like appearance. Also, the well-marked punctate pattern, in contrast to other observed Apiaceae genera, permits the identification of Daucus. Tricolporate, marginated brevicolpi.

Species.Domeykoa amplexicaulis (H.Wolff) Mathias & Constance (Plate 3, figures 21–25)

–Endemic species for Arequipa, Peru–

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, prolate shape. Medium size (28–35 µm). Tectate perforate exine, about 1.3 µm thick. Visible nexine about 0.5 µm thick. Tectum is 0.5 µm thick. Conspicuous columellae about 0.5 to 0.7 µm high. Punctate. Circular puncta less than 0.5 µm wide. Tricolporate. Marginate ectocolpi about 26 to 32 µm long and 1.5 to 2 µm wide. Colpi almost reach the apocolpium zone. Costate lalongate endopores 3 µm high and 5 to 6 µm width. Not found in polar view.

Remarks. Medium size. Prolate. Punctate ornamentation, being less conspicuous than in Daucus. Tricolporate. Colpus length (almost reaching the apocolpium zone).

Species.Eremocharis ferreyrae Mathias & Constance (Plate 3, figures 26–30)

–Endemic species for Arequipa, Peru–

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, prolate shape. Medium size (27–33 µm). Tectate perforate exine about 1.3 µm thick. Slightly visible nexine. Tectum is about 0.7 µm thick. Conspicuous columellae 0.5 µm high. Punctate. Circular puncta are less than 0.5 µm in diameter. Tricolporate. Marginate ectocolpi 25 to 28 µm long and about 1 to 2 µm wide. Colpi run over 2/3 of the grain surface. Costate lalongate endopores 3 µm high and 6 to 8 µm wide. The protuberance formed by the endopore is poorly pronounced. Not found in polar view.

Remarks. Medium size. Prolate. Tricolporate. The protuberance formed by the endopore is less pronounced in contrast to Domeykoa. Colpi longer than in Daucus but shorter than in Domeykoa.

Species.Eryngium foetidum L. (Plate 3, figures 31–35)

Description. Monad, radially symmetrical, isopolar, truncate ellipsoidal outline in equatorial view, prolate shape. Medium size (35–40 µm). Tectate perforate exine, 1.3 µm thick. Slightly visible nexine. Tectum is about 0.7 µm thick. Slightly conspicuous columellae about 0.5 µm high. Punctate. Circular puncta less than 0.5 µm in diameter. Tricolporate. Marginate ectocolpi 30 to 36 µm long and about 0.5 to 1 µm wide. Ectocolpi reach the apocolpium zone. Costate lalongate endopores about 2 to 3 µm high and about 6 to 10 µm wide. Not found in polar view.

Remarks. Medium size. Truncate ellipsoidal outline in equatorial view, prolate shape. Tricolporate. Ectocolpi reach the apocolpium zone.

APOCYNACEAE Juss.

Species.Asclepias curassavica L. (Plate 3, figures 36–40)

Description. Pollinium, bilaterally symmetrical, heteropolar, ovate and ‘tear-like’ shape. Pollinium length is 920 to 970 µm; width is about 330 to 350 µm. Corpusculum oblong and heart-shaped, smooth surface, about 410 µm long and 200 µm wide. The caudicles are attached at the back of the corpusculum and are 700 to 715 µm long. The pollen cell is symmetrical, apolar, circular amb, spheroidal shape. Large size (80–85 µm). Eutectate exine, about 3 µm thick. Visible nexine 1 µm thick. Tectum about 1 µm thick. Inconspicuous columellae. Psilate to scabrate. Inaperturate.

Remarks. Large pollinium. Compacted pollen grains show a more spherical shape compared to Philibertia. Individual grains are psilate to scabrate and inaperturate.

Species.Philibertia solanoides Kunth (Plate 4, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Pollinium, bilaterally symmetrical, heteropolar, ovate and ‘tear-like’ shape. Pollinium length is 550 to 570 µm; width is about 100 µm. Corpusculum oblong and arrow-shaped, rugate surface, about 200 µm long and 110 µm wide. The caudicles are attached laterally to the corpusculum, surface is verrucate and they are about 50 µm long. The pollen cell is asymmetrical, apolar, irregular amb, and irregular shape. Medium-sized pollen grains (40–50 µm). Eutectate exine, about 2.5 to 3 µm thick, inconspicuous columellae. The exine ornamentation is psilate to scabrate. Pollen grains are inaperturate.

Remarks. Smaller pollinium than Asclepias, differing in point of attachment of the claudicles, shape of the corpusculum, ornamentation of claudicles and corpusculum, and asymmetrical shape of pollen grains. Individual grains are psilate to scabrate and inaperturate.

ASPARAGACEAE Juss.

Species.Echeandia eccremorrhiza (Ruiz & Pav.) ined. (ex-Anthericum eccremorrhizum) (Plate 4, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, ellipsoidal amb, reniform shape. Large size (55–60 µm). Semitectate exine, about 1 µm thick. Nexine not visible. Tectum is 0.3 µm thick. Small conspicuous columellae 0.5 µm high. Reticulate heterobrochate. Irregular lumina 0.5 to 1 µm wide, decreasing in size toward the lateral axes, turning into small puncta. Simplicolumellate muri 0.5 µm wide. Monosulcate. Marginate sulcus with rounded ends, about 46 to 50 µm long and 5 to 7 µm wide.

Remarks. Large size. Reticulate heterobrochate. Thin exine compared to other monocotyledonous pollen grains observed within the Lomas. Marginate monosulcus with rounded ends.

Species.Furcraea andina Trel. (Plate 4, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Tetrad, radially symmetrical, ellipsoidal amb, decussate shape. Pollen grains of medium to large size (65–78 µm). Semitectate exine, about 3.5 µm thick. Visible nexine 1 µm thick. Tectum is about 1.5 µm thick with conspicuous columellae 2 to 2.3 µm high. Reticulate heterobrochate. Irregular lumina 2 to 5 µm wide decreasing slightly in size toward the aperture (1 µm). Simplicolumellate muri 1.2 to 1.5 µm. Monosulcate. Irregular simple sulcus, with rounded ends, is about 53 to 60 µm long and 7 to 10 µm wide.

Remarks. Tetrad. Within the Asparagaceae family, it is the only specimen for the Lomas flora that presents pollen in tetrads as dispersal units. Medium-sized to large grains. Thick exine. Reticulate heterobrochate ornamentation pattern.

Species.Oziroë biflora (ex-Fortunate biflora) (Ruiz & Pav.) Speta (Plate 4, figures 16–20)

Description. Monad, bilaterally symmetrical, ellipsoidal amb, reniform shape. Large size (50–60 µm). Semitectate exine about 1.5 µm thick. Visible nexine. Tectum is 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm high. Reticulate heterobrochate. Circular lumina, varying in size from 0.7 to 2 µm. Lumina turn into small foveolae toward the aperture. Some wider lumina are randomly dispersed between the small ones. Simplicolumellate muri about 0.5 µm wide. Monosulcate. Simple irregular sulcus, almost the length of the grain, about 47 to 50 µm long and 5 µm wide. Sulcus becomes narrow at the center of the grain.

Remarks. Large size. Rounded lumina; with scarce wider lumina in contrast to the densely dispersed smaller ones. Monosulcate. Simple irregular sulcus. Differs from Anthericum in the ornamentation pattern.

Species.Pasithea caerulea (Ruiz & Pav.) D.Don (Plate 4, figures 21–25)

Description. Monad, radially symmetrical, heteropolar, subtriangular amb, triangular obtuse convex in equatorial view, oblate shape. Medium size (30–35 µm). Semitectate exine 1.3 to 1.5 µm thick. Slightly visible thin nexine 0.3 to 0.5 µm thick. Exine becomes slightly thicker toward the mesocolpium zone. Tectum is about 0.5 µm thick. Conspicuous columellae 0.5 µm high. Reticulate heterobrochate. Lumina 0.7 to 1.2 µm wide, decreasing in size toward the aperture and at the center of the distal face. Trichotomosulcate. Simple sulcus. Each arm of the sulcus is about 12 to 15 µm long and 4 to 5 µm wide, narrowing toward the ends. Sulcus forms an arrow-like shape.

Remarks. Medium size. Subtriangular amb. Equatorial outline is triangular obtuse convex. Trichotomosulcate with simple sulcus. Trichotomosulcate. Simple sulcus. Aperture features and ornamentation pattern are diagnostic characteristics for this genus.

ASTERACEAE Bercht. & J.Presl

Species.Acmella ciliata (Kunth) Cass. (Plate 4, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical in equatorial view, prolate spheroidal shape. Medium size (27–32 µm). Tectate perforate exine, about 2 µm thick. Visible nexine 1 µm thick. Tectum is less than 0.5 µm thick. Conspicuous columellae about 0.7 µm high. Echinate. Pointed pluricolumellate echinae 4 to 5 µm high, with hook-like shape. Very thin at the top and wider at the base (3 µm). Exine surface between the base of the echinae is punctate (0.5 µm). Tricolporate. Simple ectocolpi 17 to 20 µm long and 3 to 7 µm wide with acute ends. Simple lalongate endopores 4 to 5 µm high and 8 to 9 µm wide. Endopores are not conspicuous in equatorial view.

Remarks. Medium size. Echinate with a punctate interechinae surface. Echinae in Acmella are very thin, with hook-like shape at their tips.

Species.Artemisia absinthium L. (Plate 4, figures 31–35)

Description. Monad, radially symmetrical, circular amb, elliptical in equatorial view, oblate shape. Small size (15–18 µm). Eutectate exine, about 3 to 4 µm thick. Visible nexine. Tectum is 1.2 to 1.5 µm thick and the columellae are 1.5 µm high. Exine thickness decreases toward the apertures. Microechinate, each echina is less than 0.5 µm high. Tricolporate. Simple irregular ectocolpi 12 to 15 µm long, with rounded ends, reaching the apocolpium zone. Lalongate endopores slightly costate, about 3 µm high and 5 to 6 µm wide.

Remarks. Small size. Microechinate ornamentation and the costate endopore are diagnostic characters for this genus. This morphotype is not the usual for the Asteraceae family. Ophryosporus is similar in shape, differing in length of the echinae and the costate endopore.

Species.Bidens pilosa L. (Plate 4, figures 36–40)

Description. Monad, radially symmetrical, circular to slightly subtriangular amb, elliptical in equatorial view, prolate spheroidal shape. Small size (20–25 µm). Eutectate exine, about 2 to 3 µm thick. Visible nexine 0.5 µm. Tectum is 0.5 µm thick. Columella 1 to 2 µm high. Echinate. Conical echinae 2 µm high and 1.5 µm wide at its base, also pluricolumellate; separated from each other by 2 to 3 µm. Tectum surface between echinae is scabrate. Tricolporate. Simple brevicolpi 13 to 18 µm long and 3 to 4 µm wide, with acute ends. Costate lalongate endopores, laterally acute, resembling an eye. Endopores 3 µm high and 5 to 6 µm wide.

Remarks. Small size. Circular to slightly subtriangular amb. Echinate. Tricolporate. Conspicuous endopore, resembling an eye in conjunction with the ectocolpi.

Species.Burnellia fasciculata (Wedd.) Mesfin & D.J. Crawford (ex-Coreopsis fasciculata Wedd.) (Plate 5, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical to elliptical truncate outline in equatorial view, prolate spheroidal shape. Medium size (25–30 µm). Eutectate exine 2.2 to 2.5 µm thick. Visible nexine. Tectum 1 µm thick. Conspicuous columellae 1.5 to 2 µm high. Echinate. Conical pluricolumellate echinae (4 to 5 columellae). Echinae are 4 to 5 µm high, broad at the base gradually tapering toward the apex with a more or less acute tip, about 3 to 4 µm high. Surface between echinae is punctate. Tricolporate. Irregular and slightly marginate ectocolpi 17 to 20 µm narrowing toward the apocolpium zone. Ectocolpi running along 2/3 of the grain. Simple circular endopores 4 to 6 µm in diameter.

Remarks. Small size. Elliptical to elliptical truncate outline in equatorial view. Conical shape of the echinae with 4 to 5 columellae at the base. Tricolporate. Marginate irregular ectocolpi.

Species.Cotula australis Hook. F. (Plate 5, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, triangular obtuse convex amb, circular to elliptical outline in equatorial view, prolate spheroidal shape. Small to medium size (20–26 µm). Eutectate two-layered exine of variable thickness (2 to 3.5 µm). Visible nexine about 0.2 to 0.5 µm. Tectum is 0.5 to 0.7 µm thick. Conspicuous digitate columellae of variable height (1 to 2.8 µm). Columellae strongly decrease in size toward the aperture. Echinate. Conical pluricolumellate echinae (5 to 7 columellae). Echinae about 2.5 to 3 µm long and 2 µm wide at the base. Psilate surface between echinae. Columellae capita are notably conspicuous and spread across the surface, giving the appearance of a negative reticulum. Tricolporate. Simple irregular ectocolpi 15 to 18 µm long and 4 to 5 µm wide. Long ectocolpi, even reaching the apocolpium zone. Constricted circular endopores 3 to 4 µm in diameter. Inconspicuous endopores in equatorial view.

Remarks. Small size. Triangular obtuse convex amb. Tricolporate. Constricted endopores. This genus exhibits characteristic ornamentation and exine patterns among representatives of the Asteraceae family found in the Lomas flora.

Species.Flaveria bidentis (L.) Kuntze (Plate 5, figures 11–15)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, spheroidal shape. Medium size (25–28 µm). Tectate perforate exine, about 3 µm thick. Tectum 1 µm thick. Conspicuous columellae 1.5 µm high. Echinate. Conical pluricolumellate echinae 3 to 4 µm high and 3 µm wide, with a circular hollow space at the center of the echinae bases. Surface between echinae is punctate. Tricolporate. Simple irregular long ectocolpi about 15 to 18 µm long and 5 to 6 µm wide. Ectocolpi with acute ends. Circular simple endopores 4 to 6 µm in diameter.

Remarks. Medium size. Echinate. The hollow circular space at the center of the echina base is a diagnostic feature for this genus. Tricolporate.

Species.Grindelia glutinosa (Cav.) Mart. (Plate 5, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate shape. Medium size (27–32 µm). Tectate perforate exine, about 3 to 3.2 µm thick. Visible nexine. Tectum is 1 µm thick. Conspicuous columellae 1 to 1.2 µm high. Echinate. Pluricolumellate echinae 4 µm wide at its base and 4 to 5 µm long. Echinae become thinner toward the tip (1 µm wide), overall resembling the shape of the Eiffel Tower. Each echina has 3 to 5 columellae at its base. Tricolporate to syncolporate. Simple irregular ectocolpi 25 to 32 µm long and 3 to 5 µm wide, narrowing toward the end. Some grains can be syncolporate. Circular endopores 4 to 5 µm in diameter.

Remarks. Medium size. Tricolporate to syncolporate. Echinate. Echinae shape resembling the Eiffel Tower.

Species.Onoseris odorata Hook. & Arn. (Plate 5, figures 21–25)

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, triangular to lobate amb, elliptical outline in equatorial view, perprolate shape. Large size (65–77 µm). Eutectate exine 5 to 6 µm thick. Visible nexine. Tectum is 2 to 2.5 µm thick. Digitate columellae 2 to 3 µm high, decreasing in size toward the aperture and the apocolpium zone. Microechinate. Microechinae broad at the base with a blunted tip (0.5 to 0.7 µm high) sparsely spread across the surface. Fossulate. Fossulae are 1 µm wide and about 3 to 5 µm long. Longer fossulae are placed at the intercolpium zone. Tricolporate. Long marginate ectocolpi 45 to 55 µm long and 2 to 5 µm wide. Margo with psilate surface. Endoaperture is inconspicuous due to the thick pollen wall (constricted pore). Difficult to find a perfect polar view.

Remarks. Large size. Lobate amb. Microechinate. Tricolporate. Along with Trixis, this is the other perprolate Mutiosioid (Asteraceae) pollen grain. In contrast to Trixis, the exine is thicker in Onoseris, microechinate.

Species.Ophryosporus peruvianus (J.F.Gmel.) R.M.King & H.Rob. (Plate 5, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, oblate spheroidal shape. Small size (14–17 µm). Eutectate exine, about 3 to 3.2 µm thick. Visible nexine 0.5 µm thick. Tectum is 1 µm thick. Columellae are 1.5 to 1.8 µm high. Cavate exine. Microechinate. Echinae are less than 0.5 µm high. The space between echinae is psilate. Echinae gives an undulated appearance to the exine’s contour. Morphology of echinae is difficult to characterize given their size. Tricolporate. Marginate ectocolpi 3 to 4 µm wide and 12 to 15 µm long with acute ends. Ectocolpi run 2/3 of the grain. Costate lalongate endopores 2 µm high and 4 to 5 µm wide.

Remarks. Small size. Cavate. Microechinate. Echinae give an undulated appearance to the exine contour. Space between echinae is psilate.

Species.Philoglossa peruviana D. C. (Plate 5, figures 31–35)

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, spheroidal to oblate shape. Medium size (30–38 µm). Eutectate exine 2.5 to 3 µm thick. Visible nexine. Tectum about 0.7 to 1 µm thick. Conspicuous columellae 1 to 1.5 µm high. Exine of variable size because columellae become thicker at the base of the echinae. Echinate. Thorn-like echinae 4 to 5 µm long, wider at the base (4 µm), narrowing strongly toward the tip. Each echinus is supported concentrically by 6 to 7 columellae. Space between echinae is psilate. Tricolporate. Simple irregular ectocolpi 18 to 25 µm long and about 5 to 8 µm wide. Ectocolpi ends are rounded and wide open. Simple circular endopores about 6 to 7 µm in diameter. Endopores are difficult to notice.

Remarks. Medium size. Echinate. Echinae show a thickening of the exine under each echina. Columellae concentrically organized at the base of each echina. Tricolporate.

Species.Polyachyrus annus I.M.Johns (Plate 5, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular elliptical outline in equatorial view, spheroidal shape. Medium size (25–33 µm). Eutectate exine 3.5 µm thick. Visible thick nexine. Tectum 0.5 µm. Conspicuous columellae 2.5 to 3 µm high, decreasing in size toward the aperture, increasing at the mesocolpium and apocolpium (crescentic). Fossulate. Larger fossulae are located at the mesocolpium zone, about 2 to 2.5 µm long and 1 µm wide, while the smaller fossulae, at the apocolpium zone, are about 1 to 1.5 µm long. Tricolporate. Marginate ectocolpi 5 to 7 µm wide and 22 to 27 µm long with rounded ends. Simple lalongate endopore, about 2 µm high and 4 to 6 µm wide.

Remarks. Medium size. Circular amb. Circular elliptical outline. Exine thickening pattern crescentic. Fossulate ornamentation. Columellae decreasing in size toward the aperture, increasing at the mesocolpium and apocolpium (crescentic).

Species.Proustia cuneifolia D.Don (Plate 6, figures 1–5)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, oblate spheroidal shape. Medium size (38–45 µm). Eutectate exine about 3.5 to 5 µm thick. Visible nexine (1 µm). Tectum is 1 µm thick. Conspicuous columellae about 2 to 3 µm high. Columellae decrease in size toward the apertures and the apocolpium. Fossulate. Larger fossulae (2 to 3 µm long and 1 µm wide) are mainly located at the mesocolpium zone, and the smaller ones (1.5 µm long) are placed at the apocolpium zone. Tricolporate. Marginate ectocolpi with rounded ends, about 32 to 42 µm long and 4 to 6 µm wide. Colpi almost reach the apocolpium zone. Costate lalongate endopores 4 to 5 µm high and 8 to 12 µm wide, with the extremes of each pore being acute. Endopore generate a triangular shadow inside the grain.

Remarks. Medium size. Exine thickness pattern. Similar in morphology to Polyachyrus but differing in mean size and density of the fossulae. Endopore generates a triangular shadow inside the grain. Tricolporate.

Species.Lomanthus mollendoensis (Cabrera) B.Nord. (ex-Senecio mollendoensis) (Plate 6, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for the Atiquipa Lomas (Arequipa, Peru)–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate shape. Medium size (30–37 µm). Tectate–perforate exine 2 to 2.5 µm thick. Visible nexine. Tectum 0.5 to 0.7 µm thick. Conspicuous columellae 1 to 1.5 µm high, slightly reduced toward the aperture (rapid change). Echinate. Small conical echinae 2 to 2.5 µm high, wider at the base (3 µm). Scarce echinae. The space between echinae is punctate. Tricolporate to syncolporate. Marginate ectocolpi are 5 to 8 µm wide and 27 to 35 µm long, narrowing at the apocolpium zone. Simple circular endopore, 5 to 8 µm in diameter. Endopores inconspicuous in equatorial view.

Remarks. Medium size. Tricolporate to syncolporate. Echinate. Echinae sparse in density. Columellae size decreases toward the apertures and the apocolpium.

Species.Sonchus oleraceus L. (Plate 6, figures 11–15)

Description. Monad, radially symmetrical, isopolar, hexagonal amb, rectangular obtuse convex outline in equatorial view, oblate shape. Medium size (27–36 µm). Eutectate exine 3 µm thick. Visible nexine. Tectum is 0.3 to 0.5 µm thick. Conspicuous thin columellae 2 µm high. Echinolophate. Small conical echinae 1.2 to 1.5 µm high and slightly wider at the base (2 µm), thinning at the tip (0.7 µm wide). In lateral view, echinae seem to be densely distributed; however, in plan view they are sparsely distributed. Rectangular obtuse lophae at the mesocolpium zone, about 9 to 13 µm long and 7 to 10 µm wide, while the ones at the apocolpium zones are smaller and square-like, about 3 to 5 µm long and 4 µm wide. However, the abporal lacunae are usually rounded, about 2 to 4 µm wide. Also, the ridges surrounding each lacuna are 2 µm wide. Tricolporate. Marginate ectocolpi 15 to 20 µm long and 2 to 3 µm wide, narrowing toward the apocolpium zone. Simple circular endopores 6 to 8 µm diameter, sometimes slightly lalongate. Difficult to find in equatorial view.

Remarks. Medium size. Echinolophate. Lophae with variable shapes features. Rectangular obtuse lophae at the mesocolpium zone, smaller and square-like at the apocolpium zone. However, abporal lacunae are often rounded.

Species.Stevia ovata Willd. (Plate 6, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, spheroidal shape. Small size (18–23 µm). Eutectate exine 2.5 µm thick. Visible nexine. Tectum 0.3 to 0.5 µm thick. Slightly conspicuous columellae 1.5 µm high. Echinate. Conical homogeneous echinae 2 µm long, wider at the base (2.5 µm). The distance between echinae is about 2 µm. In lateral view, echinae seem to be densely distributed; however, in plan view they are sparsely distributed. Space between echinae is psilate to slightly scabrate. Tricolporate. Marginate ectocolpi 15 to 20 µm long and 5 µm wide with rounded ends. Lalongate endopores 3 to 4 µm high and 6 to 7 µm wide, with acute lateral ends.

Remarks. Small size. Conical echinae in Stevia are very homogeneous and close to each other, in contrast to other specimens from the Asteraceae family. Tricolporate.

Species.Trixis cacalioides D.Don (Plate 6, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, perprolate shape. Medium to large size (35–56 µm). Eutectate exine 3 to 3.5 µm thick, containing two tectum layers (tectum and internal tectum). Visible nexine. ‘Sexine 1’ 1 .2 µm thick, including a tectum 0.5 µm thick and small conspicuous columellae 0.5 µm high. ‘Sexine 2’ 2 to 2.3 µm thick, containing an internal tectum 0.5 µm thick and large conspicuous columellae 1.2 to 1.5 µm high. Inner columellae decrease in size toward the apocolpium zone. Fossulate. Larger sinuous to U-shaped fossulae, located at the center of the mesocolpium zone, about 1 µm wide and 2.5 µm long. Fossulae decrease in length (0.7 to 1 µm wide and 1 µm long) and muri decrease in width toward the apocolpium zone. Tricolporate. Marginate ectocolpi 4 to 6 µm wide and 30 to 45 µm long, Margo 2.5 to 3 µm wide, with scabrate surface. Constricted lalongate endopores 2 to 3 µm wide and 8 to 12 µm high. Endopores are difficult to notice. Not found in polar view.

Remarks. Medium to large size. Perprolate shape. Presence of a tectum and an internal tectum. Fossulate ornamentation pattern (sinuous to U-shaped fossulae). Large size variability. Wider margo than in Onoseris.

Species.Aldama lanceolata (Britton) E.E.Schill. & Panero (ex-Viguiera lanceolata) (Plate 6, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, spheroidal shape. Small to medium size (20–26 µm). Tectate perforate exine 2.5 to 3 µm. Visible and thick nexine. Tectum 0.5 µm thick. Slightly conspicuous columellae 1 µm high. Echinate. Pluricolumellate conical echinae (4 to 5 columellae) 4 to 4.5 µm long, also wider at its base (2 to 2.3 µm) with a hollow circular space at the center. Space between echinae is punctate. Tricolporate. Simple ectocolpi 15 to 18 µm long and 5 to 6 µm wide. Simple lalongate endopores 3 to 5 µm high and 7 to 8 µm wide, with acute ends.

Remarks. Small size. Thick nexine. Pluricolumellate conical echinae. Similar to Flaveria, but the hollow space at the center of the base of the echinae are less wide than in Vigueria, also differing in the exine pattern. Tricolporate.

Species.Villanova oppositifolia Lag. (ex-Vasquezia oppositifolia) (Plate 6, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, oblate spheroidal shape. Small to medium size (20–27 µm). Tectate perforate exine 2.5 µm thick. Visible nexine (1 µm). Tectum about 0.5 µm thick. Conspicuous columellae 1 µm high. Echinate. Pluricolumellate conical to hook-shaped echinae 3 to 4 µm high, wider at the base (3.5 to 4.2 µm). Columellae arranged concentrically at the base of echinae. Space between echinae is punctate. Tricolporate. Marginate ectocolpi 18 to 22 µm long and 3 to 4 µm wide, narrowing toward the apocolpium zone. Endopores are lalongate, about 4 to 5 µm high and 8 to 10 µm wide. The extremes of each pore are acute, narrowing at its end.

Remarks. Small to medium-sized grain. Circular amb. Circular outline in equatorial view. Oblate spheroidal shape. Echinate. Conical to hook-shaped echinae. Space between echinae is punctate. Tricolporate, marginate.

Species.Wedelia hoffmanniana Bruns (Plate 6, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, oblate shape. Small size (18–24 µm). Tectate–perforate exine, about 2.5 to 3 µm thick. Visible nexine. Tectum 0.7 µm thick. Conspicuous columellae 1 to 1.5 µm high. Echinate. Pluricolumellate conical to thorn-like echinae 3.2 to 4 µm long. The base of each echina is about 1.8 to 2 µm wide. Columellae arranged concentrically at the base of the echina. Space between echinae is punctate. Columellae arranged concentrically at the base of each echinus. Tricolporate and brevicolpate. Simple irregular ectocolpi 14 to 18 µm long and 2 to 4 µm wide, narrowing toward the ends. Endopores are circular, about 4 µm in diameter.

Remarks. Small size. Brevicolpate. Echinate. Pluricolumellate conical to thorn-like echinae. Similar to Flaveria and Vigueria in shape but the ectocolpi are shorter in Wedelia.

BEGONIACEAE C.Agardh

Species.Begonia octopetala L'Hér. (Plate 7, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate shape. Small size (12–22 µm). Eutectate exine 1 µm thick. Slightly visible nexine. Tectum is 0.5 µm thick. Inconspicuous columellae (less than 0.5 µm high). Striate. Long continuous thin striae (less than 0.5 µm wide). Striae run homogeneously from pole to pole. Ornamentation pattern is subtle. Tricolporate. Slightly marginate ectocolpi with acute ends about 2 to 3 µm wide and 10 to 20 µm long, reaching the apocolpium zone. Costate lalongate endopores 2 to 3 µm high and 4 to 6 µm wide. Exine separates toward the apertures forming small fastigia (0.5 µm high).

Remarks. Small size. Striate, inconspicuous columellae. Subtle ornamentation pattern. Tricolporate. Well-defined endocostae and fastigia.

BIGNONIACEAE Juss.

Species.Argylia radiata (L.) D.Don (Plate 7, figures 6–10)

Description. Monad, radially symmetrical, pentagonal amb, elliptical truncate outline in equatorial view, prolate shape. Large size (75–80 µm). Semitectate exine 2.5 to 3 µm thick. Visible nexine, increasing in thickness at the mesocolpium zone. Tectum is 0.5 µm thick. Conspicuous columellae 1.5 to 1.7 µm high. Columellae with visible capita. Reticulate. Heterobrochate reticulum, with irregular lumina (1 to 3 µm wide). Simplicolumellate muri 0.5 µm. Muri around each lumina are composed of 3 to 5 columellae. Tricolpate. Pontoperculate. Simple irregular ectocolpi 60 to 65 µm long and about 30 to 35 µm wide. Colpi length is 2/3 of the grain. Pontopercula are as wide as the apertures, about 15 to 25 µm but thinning at the attachment point (apocolpium). Pontopercula gives the impression of a geminicolpate condition (stephanocolpate).

Remarks. Large size. Pentagonal amb, elliptical truncate outline in equatorial view. Pontoperculate, giving the impression of a stephanocolpate condition. Difference in width between mesocolpium and pontoperculum helps in identifying this condition.

Species.Tourrettia lappacea (L'Hér.) Willd. (Plate 7, figures 11–15)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate shape. Large size (50–55 µm). Eutectate exine 1.7 to 2 µm thick. Slightly visible nexine. Thin tectum 0.2 to 0.3 µm thick. Conspicuous columellae 0.7 to 1 µm high. Fossulate. Fossulae 0.3 to 0.5 µm wide with variable shape. Larger fossulae 1 to 1.2 µm long, C-shaped, or worm-like, while the smaller ones are circular to linear, about 0.5 to 0.7 µm long. Tricolpate. (Pont)operculate. Simple irregular colpi 42 to 46 µm long and 3 to 10 µm wide, with rounded ends. The exine at the attachment area between colpi and opercula has an irregular pattern.

Remarks. Large size. Circular amb, elliptical outline in equatorial. Fossulate. Fossulae with variable shape. Tricolpate. (Pont)operculate.

BORAGINACEAE Juss.

Species.Tournefortia schomburkgii A. DC. (Plate 7, figures 16–20)

Description. Monad, radially symmetrical, isopolar, circular amb, circular to elliptical outline in equatorial view, oblate spheroidal shape. Medium size (30–35 µm). Eutectate exine 2 to 2.5 µm thick. Visible nexine (1 µm thick). Tectum 0.5 to 0.7 µm thick. Columellae are about 0.5 to 0.8 µm high. Exine thickens toward the aperture. Verrucate. Irregular verrucae 1 to 3 µm wide and 1 µm high, not homogeneous. Tricolporate to stephanocolporate (four colpori). Marginate ectocolpi with acute ends, about 2 to 4 µm wide and about 27 to 30 µm long. Margo with psilate ornamentation. Costate circular endopores about 4 to 5 µm in diameter.

Remarks. Medium size. Ornamentation pattern is verrucate (irregular size). Variable number of apertures (3–4 colpori).

BRASSICACEAE Burnett

Species.Brassica rapa L. (Plate 7, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, oblate shape. Small size (15–22 µm). Semitectate exine 2 µm thick. Visible nexine. Tectum is about 0.3 to 0.7 µm thick. Conspicuous columellae are 0.7 to 1 µm high. Columellae decrease in size toward the apertures. Reticulate heterobrochate. Larger irregular lumina located at the mesocolpium zone (1.2 to 1.5 µm wide). Smaller irregular lumina placed at the apocolpium zone, about 0.5 to 1 µm. Simplicolumellate muri 0.5 to 0.6 µm wide. Tricolpate. Simple irregular colpi with rounded ends, about 8 to 15 µm long and 4 µm wide.

Remarks. Small size. Reticulate heterobrochate. Simplicolumellate muri. Columellae decreasing in size toward the apertures. Tricolpate.

Species.Capsella bursa-pastoris (L.) Medik. (Plate 7, figures 26–30)

Description. Monad, radially symmetrical, isopolar, circular amb, circular to elliptical outline in equatorial view, oblate spheroidal shape. Small size (13–18 µm). Semitectate exine 1.5 µm thick. Visible nexine. Tectum 0.4 to 0.5 µm thick. Small conspicuous columellae 0.3 to 0.5 µm high. Columellae decrease in size toward the apertures. Reticulate heterobrochate. Larger irregular lumina are located at the mesocolpium zone, about 0.7 to 1 µm wide, while the smaller ones are placed at the mesocolpium zone (0.5 µm wide), with a more circular shape, resembling a puncta. Simplicolumellate muri 0.5 µm thick and. Tricolpate. Simple irregular colpi with rounded ends, about 4 to 5 µm wide and 10 to 15 µm long.

Remarks. Small size. Reticulate heterobrochate. Tricolpate. Similar features than in Brassica.

Species.Lepidium chichicara Desv. (Plate 7, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate shape. Small size (16–22 µm). Semitectate exine 1.5 µm thick. The tectum is about 0.5 µm thick and the columellae are 0.7 to 1 µm high. Columellae decrease in size toward the apertures. Reticulate heterobrochate. Larger irregular lumina located at the mesocolpium zone, about 1 to 1.5 µm wide, while the smaller ones are placed at the apocolpium zone, being about 0.5 to 0.7 µm. Simplicolumellate muri 0.3 to 0.5 µm wide. Tricolpate. Simple colpi with rounded ends 2 to 3 µm wide and 12 to 17 µm long.

Remarks. Small size. Reticulate heterobrochate. Simplicolumellate muri. Tricolpate. Similar morphology as in Brassica.

Species.Lobularia maritima (L.) Desv. (Plate 7, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, subprolate to prolate shape. Small to medium size (10–27 µm). Semitectate exine 2 to 2.5 µm thick. Visible nexine (0.7 to 0.8 µm thick). Tectum 0.3 to 0.5 µm thick. Conspicuous columellae are 0.8 to 1 µm high. Columellae decrease in size toward the apertures. Reticulate and heterobrochate. Larger lumina located at the mesocolpium zone, about 1.5 to 2 µm wide, having a pentagonal shape, while the smaller ones are about 0.8 to 1 µm wide with more variable and heterogeneous shapes. Simplicolumellate muri 0.3 to 0.5 µm wide. Tricolpate. Simple colpi with rounded ends, about 2 to 3 µm wide and about 10 to 25 µm long.

Remarks. Small to medium size. Elliptical truncate outline in equatorial view. Reticulate heterobrochate. Well-defined individual columella. Tricolpate.

Species.Mathewsia peruviana O.E.Schulz (Plate 8, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, apolar, circular to subtriangular amb. Medium size (25–30 µm). Semitectate exine 3.5 µm thick. Visible nexine. Thin tectum 0.3 µm thick. Conspicuous columellae 2.5 µm high. Sexine is considerably thicker than nexine. Reticulate. Heterobrochate. Irregular lumina 1 to 4 µm wide. Simplicolumellate muri 0.5 to 0.7 µm wide. Inaperturate.

Remarks. Medium size. Reticulate heterobrochate. Inaperturate.

Species.Mostacillastrum gracile (Wedd.) Al-Shehbaz (ex-Sisymbrium gracile) (Plate 8, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical to elliptical obtuse outline in equatorial view, prolate spheroidal shape. Small to medium size (20–30 µm). Semitectate exine 2 to 2.5 µm thick. Visible nexine. Thin tectum, less than 0.5 µm thick. Conspicuous columellae 1 to 1.5 µm high. Columellae sharply decrease in size toward the apertures. Sexine is considerably thicker than nexine. Reticulate. Heterobrochate. Lumina shapes are irregular. Larger lumina located at the mesocolpium zone (1.5 to 2 µm wide) and smaller ones at the apocolpium zone (0.7 to 1 µm wide). Simplicolumellate muri 0.5 µm wide. Tricolpate. Simple long colpi with acute ends about 20 to 28 µm long and 2 to 5 µm wide. Slightly irregular colpi, constricted at the equator (in equatorial view). Presence of colpi membranes.

Remarks. Medium size. Ornamentation pattern is reticulate heterobrochate. Tricolpate. Presence of colpi membranes.

BROMELIACEAE Juss.

Species.Puya ferruginea (Ruiz & Pav.) L.B.Sm. (Plate 8, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (40–45 µm). Semitectate exine 1.2 to 1.5 µm thick. Visible nexine. Thin tectum 0.2 to 0.3 µm thick. Conspicuous columellae 0.7 to 0.8 µm high. Columellae decrease in size toward the lateral axes of the grain. Reticulate. Heterobrochate. Lumina with variable shapes. Larger lumina 2 to 2.5 µm, located at the center of the distal and equatorial faces, decreasing in size toward the lateral axes of the grain (0.5 to 1 µm wide). Simplicolumellate muri 0.5 to 0.7 µm wide. Monosulcate. Marginate sulcus with rounded ends about 5 µm wide, and 32 to 38 µm long.

Remarks. Medium size. ellipsoidal amb, reniform shape. Reticulate heterobrochate. Exine decreases in thickness. Monosulcate.

Species.Tillandsia latifolia Meyen (Plate 8, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (35–40 µm). Semitectate exine 2 to 2.2 µm. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm high. Reticulate. Heterobrochate. Lumina with variable shape and size. Larger lumina located at the center of the distal face and the equator (1.5 to 2 µm wide). Lumina decrease in width toward the aperture and the lateral axes of grain (0.7 to 1 µm). Simplicolumellate muri 0.3 to 0.5 µm wide. Monosulcate. Simple to slightly marginate sulcus with rounded ends, about 30 to 37 µm long and 5 to 7 µm wide. Irregular sulcus constricted at the center.

Remarks. Medium size. Ellipsoidal amb, reniform shape. Monosulcate. Irregular sulcus. Exine with constant thickness compared to Puya.

CACTACEAE Juss.

Species.Armatocereus matucanensis Backeb. (Plate 8, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate spheroidal shape. Large size (77–95 µm). Semitectate exine 2 µm thick. Visible nexine. Tectum is 0.5 µm thick. Visible but not differentiated columellae about 1 µm high. Foveolate and microechinate. Circular foveolae at the apocolpium zone (1 µm in diameter), fusing at the mesocolpium zone (1.5 µm long) with a worm-like shape. Small conical microechinae 0.8 to 1 µm high, sparsely dispersed across the surface. Tricolpate. Slightly marginate ectocolpi with acute ends 18 to 25 µm wide in polar view, and 68 to 85 µm long. In equatorial view, colpi seem to be constricted.

Remarks. Large size. Elliptical truncate outline in equatorial view. Foveolate and microechinate. Characteristic microechinae density and shape. Constricted condition of the aperture in equatorial view.

Species.Borzicactus fieldianus Britton & Rose (Plate 8, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for the Peruvian desert–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical to elliptical truncate outline in equatorial view, prolate shape. Large size (55–68 µm). Tectate perforate to 1.7 to 2 µm thick. Visible nexine. Tectum 0.5 to 0.6 µm thick. Visible but not differentiated columellae 0.8 to 1 µm high. Punctate and microechinate. Circular puncta less than 1 µm, widely dispersed. Small conical microechinae about 0.3 to 0.5 µm high, sparsely distributed across the surface. Tricolpate. Marginate irregular colpi with acute ends, 8 to 15 µm wide in polar view, and 45 to 50 µm long in equatorial view. Colpi seem to be constricted in equatorial view.

Remarks. Large size. Punctate and microechinate. Tricolpate. In contrast to Armatocereus, perforations (puncta) are considerably smaller, as well as the size of the microechinae.

Species.Corryocactus brachypetalus (Vaupel) Britton & Rose (Plate 8, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, circular amb, elliptical truncate outline in equatorial view, prolate shape. Medium to large size (45–55 µm). Semitectate exine 2 µm thick. Visible nexine (1 µm thick). Tectum 0.5 to 0.7 µm thick. Conspicuous columellae 0.5 µm high. Columellae decrease in size toward the apertures. Foveolate. Circular foveola 1 µm in diameter, widely dispersed across the surface. Some foveolae fuse at the apocolpium zone (1.2 to 1.5 µm wide). Tricolpate. Marginate colpi with acute ends, about 10 to 15 µm wide in polar view, and 40 to 48 µm long. In the equatorial view, colpi seem to be constricted.

Remarks. Medium to large size. Foveolate. Tricolpate. In contrast to Armatocereus and Borzicactus, this genus lacks microechinate ornamentation (in light transmission microscopy).

Species.Cumulopuntia sphaerica (C.F.Först.) E.F.Anderson (Plate 8, figures 36–40)

–Endemic species for Peru–

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Large size (87–97 µm). Semitectate exine 3 µm thick. Visible nexine. Tectum 0.8 to 1 µm thick. Conspicuous columellae 1 to 1.2 µm high. Columellae slightly decrease in size toward the apertures. Foveolate. Circular foveolae 1 to 1.2 µm in diameter, but decreasing in size toward the aperture, turning into puncta (less than 1 µm in diameter). Simplicolumellate muri 0.5 to 0.7 µm wide. Pantoporate (15–20 pores). Simple circular to elongated pores, about 9 to 12 µm in diameter. Some pores are slightly lalongate, giving the appearance of a brevicolpus.

Remarks. Large size. Foveolate. Ornamentation pattern. Pantoporate, 15–20 pores slightly lalongate.

Species.Trichocereus macrogonus (Salm-Dyck) Riccob. (ex-Echinopsis peruviana) (Plate 9, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate shape. Large to very large size (90–110 µm). Semitectate exine 2 µm thick. Visible nexine (1 µm thick). Tectum is 0.5 to 0.7 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Exine sharply decreases in thickness toward the apertures. Foveolate and microechinate. Irregular foveolae 1 to 1.2 µm wide, dispersed across the surface. Within the foveolae, there are dispersed puncta less than 0.8 µm in diameter. Small conical microechinae 1 µm high, sparsely distributed across the surface. Tricolpate. Simple to slightly marginate colpi with acute ends, about 70 to 83 µm long and 33 to 40 µm wide in polar view, but 8 to 10 µm wide in equatorial view.

Remarks. Large to very large size. Foveolae arrangement. Tricolpate. Simple to slightly marginate colpi.

Species.Haageocereus acranthus (Vaupel) Backeb. (Plate 9, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate shape. Large size (65–73 µm). Semitectate exine 2 to 2.3 µm thick. Visible nexine. Tectum is 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.8 µm high. Foveolate and echinate. Circular foveolae 1 µm in diameter, widely dispersed across the surface. Within foveolae, there are puncta of less than 0.8 µm. Small conical echinae 1 µm high, densely dispersed. Tricolpate. Slightly marginate colpi with acute ends, about 36 to 45 µm long and about 15 to 18 µm wide in polar view. Colpi seem to be constricted in equatorial view.

Remarks. Large size. Thick exine. Ornamentation pattern with dense presence of echinae across the surface. Foveolate and echinate. Tricolpate.

Species.Loxanthocereus sextonianus (Backeb.) Backeb. (ex-Loxanthocereus gracilis) (Plate 9, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, spheroidal to prolate shape. Large size (65–70 µm). Tectate perforate exine 2 to 2.2 µm thick. Visible nexine (1 µm). Tectum is about 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm high. Sexine sharply decreases toward the apertures. Punctate and echinate. Circular puncta 0.5 to 0.7 µm in diameter, dispersed across the surface. Conical echinae 1 to 1.2 µm high, sparsely dispersed across the surface (spaced 4 to 5 µm). Tricolpate. Marginate colpi of rounded ends, about 5 to 15 µm wide, and 52 to 67 µm long. Colpi seem to be constricted in equatorial view. Very reduced apocolpium zone.

Remarks. Large size. Punctate and echinate. Tricolpate. Similar to Haageocereus, but differing in the density of the echinae (less dense for this genus), rounded ends of the colpi, and sexine thickness decrease.

Species.Neoraimondia arequipensis (Meyen) Backeb. (Plate 9, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical acuminate outline in equatorial view, prolate shape. Large size (57–65 µm). Tectate perforate exine 1.7 to 2 µm. Visible nexine. Tectum is 0.5 µm thick. Visible but not differentiated columellae 0.5 to 0.7 µm high. Punctate. Circular to irregular puncta 0.3 to 0.7 µm in diameter, densely dispersed across the surface. Tricolpate. Marginate colpi with acute ends, about 53 to 60 µm long and 10 to 15 µm wide at polar view and 4 to 6 µm at equatorial view. Colpi seem to be constricted in equatorial view.

Remarks. Large size. Punctate. Tricolpate. Similar to Corryocactus but differing in exine thickness, diameter of the perforation (puncta) pattern, and the equatorial outline.

Species.Opuntia stricta (Haw.) Haw. (Plate 9, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Large size (63–72 µm). Semitectate exine 4 µm thick. Visible nexine. Tectum is 0.5 to 0.7 µm thick. Conspicuous columellae 2 to 2.2 µm high. Columellae sharply decrease in size toward the apertures. Columellae with flat capita. Reticulate (negative reticulum). Heterobrochate. Square-like lumina 1 to 1.5 µm wide but decreasing in size toward the aperture. Simplicolumellate muri 0.5 µm wide. Pantoporate (10 to 12 pores). Circular to slightly elongated ectopores, about 12 to 15 µm in diameter. Costate circular to elongated endopores 15 to 18 µm in diameter. Apertures are considerably separated (8 to 10 µm). Some pores are slightly lalongate, giving the appearance of a brevicolpus. The exine slightly separates toward the apertures forming fastigia (0.5 µm high).

Remarks. Large size. Ornamentation pattern is reticulate (negative reticulum). Pantoporate (10 to 12 pores). Wide distance between apertures. Costate endopores. Presence of fastigia.

Species.Haageocereus bylesianus (Andreae & Backeb.) Lodé (ex-Pygmaeocereus bylesianus Andreae & Backeb). (Plate 9, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, quadrangular amb. Large size (70–75 µm). Tectate perforate to semitectate, about 2.5 µm thick. Visible nexine. Tectum 0.5 to 0.7 µm thick. Visible but not differentiated columellae 0.5 to 0.7 µm high. Sexine slightly decreases toward the apertures. Regular weakened exine areas at the apocolpium zone. Punctate and microechinate. Circular to irregular puncta 0.5 µm in diameter. Also, across the surface there are foveolae less than 1 µm in diameter. Echinae are about 0.5 µm high, densely widespread across the surface. Stephanocolpate (4–5 colpi). Simple colpi with acute ends about 18 to 22 µm wide and 50 to 55 µm long. Not found in equatorial view.

Remarks. Large size. Quadrangular amb. Punctate and microechinate. Stephanocolpate (4–5 colpi). Only stephanoaperturate genus for the family Cactaceae. In contrast to other genera, the echinae are smaller, less than 1 µm high.

Species.Weberbauerocereus rauhii Backeb. (Plate 9, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate shape. Large size (57–65 µm). Semitectate exine about 3 µm thick. Visible thick nexine about 1.2 µm thick. Tectum is 0.5 µm thick. Columellae are about 1.3 µm high. Sexine decreases toward the apocolpium zone. Foveolate and echinate. Circular foveolae 1 µm in diameter, abundant at the apocolpium zone. Puncta within foveolae less than 0.7 µm. Conical echinae are less than 1 µm high, about 0.5 to 0.8 µm. Some echinae have rounded tips. Densely distributed echinae. Tricolpate. Simple colpi 48 to 55 µm long, with rounded ends; about 12 to 20 µm wide in polar view, and 3 to 5 µm in equatorial view. Reduced apocolpium zone.

Remarks. Large size. Foveolate and echinate. Tricolpate. Simple colpi. Ornamentation pattern, with densely distributed echinae.

CALCEOLARIACEAE Raf. ex Olmstead

Species.Calceolaria tripartita Ruiz & Pav. (Ex Calceolaria pinnata) (Plate 9, figures 36–40)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, oblate spheroidal shape. Small size (15–20 µm). Semitectate exine 1 µm thick. Tectum less than 0.5 µm thick. Conspicuous columellae 0.5 to 0.6 µm high. Microreticulate. Homobrochate. Circular lumina 0.5 to 0.7 µm wide. Simplicolumellate muri 0.5 µm wide or less. Tricolporate. Marginate ectocolpi with rounded ends, about 10 to 12 µm long and 3 to 5 µm wide. Costate circular endopores about 4 to 5 µm in diameter. Also, the exine starts to separate near the apertures, forming fastigia 0.5 µm high.

Remarks. Small size. Microreticulate. Homobrochate. Tricolporate. Well-defined marginate ectocolpi and costate endopores, in conjunction with the circular microreticulate ornamentation pattern and the presence of fastigia.

CAMPANULACEAE Juss.

Species.Lobelia decurrens Cav. (Plate 10, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate to elliptical emarginate outline in equatorial view, oblate to prolate shape. Medium size (25–32 µm). Tectate perforate exine 1.5 µm thick. Visible nexine, not reaching the ectoapertures. Tectum 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Punctate. Circular puncta less than 0.5 µm in diameter, widely dispersed across the surface. Tricolporate. Simple long ectocolpi with rounded ends, about 22 to 25 µm long and 3 to 5 µm wide. Very small apocolpium zone. Costate lalongate endopores 5 µm high and 7 to 8 µm wide. Exine separates toward the apertures, forming fastigia with the nexine not reaching the endoaperture (Atrium-like feature).

Remarks. Medium size. Punctate. Tricolporate. The well-defined stratification of the exine, reduced apocolpium zone, and the almost projectate endopore due to the fastigia are diagnostic characteristics for this genus. Fastigia with atrium-like features.

CAPPARACEAE Juss.

Species.Morisonia petiolaris (Kunth) Christenh. & Byng (ex-Capparis prisca) (Plate 10, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate spheroidal shape. Medium size (25–28 µm). Tectate–perforate exine 2 µm thick. Visible nexine, being more conspicuous close to the apertures. Tectum 0.5 to 0.7 µm. Slightly conspicuous columellae 0.5 to 0.8 µm high. Exine becomes thicker at the apocolpium zone and the apertures (2.5 to 2.7 µm), and thinner toward the mesocolpium. Punctate and scabrate. Circular puncta less than 0.5 µm in diameter, densely concentrated at the apocolpium zone. The space between puncta is scabrate. Large scabra 1 to 1.5 µm long, densely located at the mesocolpium zone. Tricolporate to stephanocolporate (four colpori). Slightly marginate ectocolpi with rounded ends, about 20 to 24 µm and 5 µm wide. Very long colpi, leaving a very reduced apocolpium zone. Costate lalongate endopores 4 to 5 µm high and 7 to 10 µm wide. Exine slightly separates toward the apertures, forming small fastigia.

Remarks. Medium size. Punctate and scabrate. Tricolporate to stephanocolporate (four colpori). This grain can be recognized by the distribution of the puncta and scabrae across the surface, associated with the notable thickening of the exine at the apocolpium zone, the aperture type with prominent endopores, and aperture number (3–4).

CAPRIFOLIACEAE Juss.

Species.Valeriana chaerophylloides Sm. (Ex-Astrephia chaerophylloides) (Plate 10, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, ellipsoidal truncate outline in equatorial view, oblate spheroidal shape. Medium size (36–48 µm). Tectate perforate exine 2 to 2.5 µm thick. Exine thickness increases at the base of supratectal elements. Visible nexine (0.7 to 1 µm thick). Tectum 0.5 to 0.7 µm thick. Slightly conspicuous columellae 0.8 to 1 µm, tectum about 1 µm. Punctate and echinate. Circular puncta less than 0.5 µm in diameter, widely distributed across the surface. Conical echinae 0.7 to 1 µm high, densely distributed. Tricolpate to stephanocolpate (four brevicolpi). Marginate brevicolpi with rounded ends, about 10 to 15 µm long and 3 to 7 µm wide. Ornamented aperture membrane.

Remarks. Variable medium-sized to large grain and aperture number 3–4. Punctate and echinate. Tricolpate to stephanocolpate (four brevicolpi). The ornamentation pattern composed of puncta and echinae is similar to the one found in the family Cactaceae. However, Valeriana has marginate brevicolpi, ornamented aperture membrane and well-defined and widely distributed conical echinae.

CARICACEAE Dumort.

Species.Vasconcellea candicans (A.Gray) A.DC. (Plate 10, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, bilaterally symmetrical, heteropolar, subtriangular amb, elliptical truncate outline in equatorial view, prolate shape. Medium size (35–40 µm). Tectate–perforate exine 2 µm thick. Visible nexine. Tectum is 0.5 µm thick. Inconspicuous or densely accommodated columellae 1 µm high. Psilate and locally puncate. Circular puncta less than 0.5 µm in diameter are located at the apocolpium zone. Tricolporate and syncolporate. Marginate ectocolpi with rounded ends, about 32 to 37 µm long and 3 to 7 µm wide. Ectocolpi with well-defined margo 1 to 1.3 µm thick. Constricted colpi in equatorial view. Colpi fuses in only one pole, making the grain heteropolar. Costate lalongate endopores lalongate, about 3 to 4 µm high and 12 to 16 µm wide. Endopore with acute lateral axes. Exine separates toward the apertures, forming fastigia. Presence of an aperture membrane (slightly ornamented).

Remarks. Medium size. Bilaterally symmetrical. Heteropolar, subtriangular amb. Psilate and locally puncate. Puncta located only in the apocolpium zone. Tricolporate and syncolporate. Syncolporate in only one pole.

CARYOPHYLLACEAE Juss.

Species.Cerastium glomeratum Thuill. (Plate 10, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (34–40 µm). Semitectate exine 3 to 3.2 µm thick. Visible nexine. Tectum is 1 µm thick. Conspicuous columellae 1 to 1.7 µm high. Columellae decrease in size toward the apertures. Microreticulate. Heterobrochate. Circular to irregular lumina 0.7 to 1 µm in diameter. Simplicolumellate muri 0.5 µm wide. Pantoporate (15 pores). Simple circular ectopores 4 to 6 µm in diameter. Operculated ectopores. Opercula with gemmate-like ornamentation. Costate circular endopores 4 to 5 µm in diameter.

Remarks. Medium size. Microreticulate. Heterobrochate. Circular to irregular lumina. Pantoporate (15 operculated pores). Gemmate-like opercula. Costate endopores.

Species.Drymaria divaricata Kunth. (Plate 10, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (30–37 µm). Tectate–perforate exine 2 to 2.2 µm thick. Visible nexine. Tectum is 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm thick. Columellae slightly decrease in size toward the apertures. Fossulate. Circular to irregular fossulae 0.5 to 0.7 µm in diameter. Larger ones are worm-like shaped, about 0.7 µm wide and 1 µm long. Pantoporate (15 to 18 pores). Simple circular pores, about 3 to 5 µm in diameter. Simple to costate endopores.

Remarks. Medium size. Fossulate. Notable differentiation between larger and smaller lumina. Pantoporate (15 to 18 pores). In contrast with Cerastium, the pores of Drymaria are not operculate.

Species.Paronychia setigera (Gillies ex Hook. & Arn.) F.Herm. (Plate 10, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Small size (15–18 µm). Tectate–perforate exine 1.5 µm thick. Visible nexine. Tectum is 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm high. Columellae slightly decrease in size toward the apertures. Punctate. Circular puncta less than 0.5 µm in diameter, densely dispersed across the surface. Pantoporate (up to 12 pores). Simple circular ectopores 3 to 4 µm in diameter. Circular costate endopores, about 5 to 7 µm in diameter. The exine separates toward the apertures, forming vestibula.

Remarks. Small size. Punctate. Pantoporate (up to 12 pores). Wide pore size in relation to the grain. Presence of vestibula.

Species.Silene gallica L. (Plate 10, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (30–40 µm). Semitectate exine 3.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 2 to 2.2 µm high. Columellae slightly decrease in size toward the aperture. Reticulate. Homobrochate. Square-like homogeneous lumina 1 to 1.2 µm wide. Simplicolumellate muri 0.5 µm wide. Constant lumen/murus ratio. Pantoporate (25–30 pores). Annulate circular ectopores, about 4 to 5 µm in diameter. Costate circular endopores, slightly smaller than the ectopores (3 µm in diameter).

Remarks. Medium, variable size. Ornamentation pattern (constant lumen/murus ratio). Pantoporate (25–30 circular pores). Annulate ectoaperture.

Species.Spergularia congestifolia I.M.Johnst. (Plate 11, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, oblate spheroidal shape. Small size (18–21 µm). Tectate–perforate exine 1.3 to 1.5 µm thick. Slightly visible nexine. Tectum is 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Columellae slightly decrease in size toward the apertures. Punctate. Circular puncta 0.3 to 0.5 µm in diameter, homogeneously dispersed across the surface. Tricolpate. Simple irregular colpi with rounded ends, about 5 µm wide and 14 to 16 µm long. Nexine does not reach the apertures, forming an atrium-like feature. Aperture membrane slightly ornamented.

Remarks. Small size. Ornamentation pattern (punctate). Tricolpate. (irregular colpi). Atrium-like feature. Aperture membrane slightly ornamented.

Species.Stellaria ovata Willd. ex D.F.K.Schltdl. (Plate 11, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular to slightly hexagonal amb. Medium size (30–40 µm). Tectate–perforate exine 3 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 2 µm high. Columellae decrease in size toward the apertures. Punctate and gemmate. Circular puncta 0.3 to 0.5 µm in diameter, densely dispersed across the surface. Rounded gemmae 1 µm high are sparsely dispersed across the surface, but decreasing in size toward the apertures. Pantoporate (12 to 15 pores). Simple circular ectopores 4 to 6 µm in diameter. Operculate ectopores. Opercula with gemmate ornamentation, gemmae clustered in groups of five to seven. Costate circular endopores, same width as the ectopores (4 to 5 µm in diameter).

Remarks. Medium size. Circular to slightly hexagonal amb. Punctate and gemmate, gemmae clustered in groups of five to seven. Pantoporate (12 to 15 operculated pores). Simple endospores, costate endospores.

CELASTRACEAE R.Br.

Species.Maytenus orbicularis (Humb. & Bonpl. ex Schult.) Loes. (ex-Maytenus octogona) (Plate 11, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical truncate outline in equatorial view, prolate shape. Small size (12–18 µm). Tectate–perforate exine, about 1.5 to 2 µm thick. Visible nexine. Tectum is 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm high. Columellae decrease in size toward the apertures. Microreticulate. Circular lumina 0.3 to 0.5 µm in diameter, densely dispersed across the surface. Tricolporate. Marginate ectocolpi with acute ends, about 2 to 2.5 µm wide and 9 to 14 µm long. Wide apocolpium zone. Colpi constricted at the equator. Geniculate in equatorial view. Costate lolongate endopores, about 5 to 6 µm high and 2 µm wide. Difficult to find in polar view.

Remarks. Small size. Geniculate in equatorial view. Subtriangular amb, elliptical truncate outline in equatorial view, Microreticulate. Tricolporate. Lolongate endopores.

CLEOMACEAE Airy Shaw

Species.Cleome chilensis DC. (Plate 11, figures 16–20)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical to elliptical truncate outline in equatorial view, oblate shape. Small size (12–15 µm). Tectate perforate exine 1.2 to 1.5 µm thick. Visible nexine. Tectum is 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Microreticulate. Circular lumina 0.3 to 0.7 µm in diameter, densely dispersed across the surface. Tricolporate. Marginate ectocolpi with rounded ends, about 2 µm wide and 8 to 10 µm long. Reduced apocolpium zone. Costate lalongate endopores, about 3 to 4 µm high and 6 to 8 µm wide. The exine slightly separates toward the apertures forming fastigia.

Remarks. Small size. Ornamentation pattern is microreticulate. Tricolporate. Reduced apocolpium zone. Fastigiate.

COMMELINACEAE Mirb.

Species.Commelina tuberosa L. (ex-Commelina fasciculata) (Plate 11, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, bilaterally symmetrical, heteropolar, reniform shape. Medium size (35–42 µm). Eutectate exine 1 to 1.5 µm thick, thickening slightly toward the distal face. Nexine not visible. Tectum is 0.5 to 0.7 µm thick. Inconspicuous columellae. Sexine increases in thickness at the distal face. Echinate. Conical echinae with variable height. Larger echinae are 2 to 2.5 µm high, wider at the base (3 µm), densely dispersed across the surface. Smaller echinae (1 to 1.5 µm high) located at the aperture’s margin and at the distal face. Change from larger to smaller echinae is sudden. Monosulcate. Simple sulcus with rounded ends, about 4 to 8 µm wide and 33 to 42 µm long, with rounded ends.

Remarks. Medium size. Heteropolar, reniform shape. Echinate. Conical echinae with variable height. Simple monosulcus. This genus represents the only monocotyledonous–monosulcate pollen grain with echinate ornamentation within the studied Lomas flora.

CONVOLVULACEAE Juss.

Species.Cuscuta grandiflora Kunth (Plate 11, figures 26–30)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical to elliptical truncate outline in equatorial view, prolate shape. Medium size (25–35 µm). Semitectate exine 2 to 2.5 µm. Visible nexine. Tectum is 0.5 to 0.7 µm thick. Conspicuous columellae 1 to 1.3 µm high. Columellae slightly decrease in size toward the apertures and the equator. Reticulate. Heterobrochate. Irregular lumina 1 to 1.5 µm wide, aleatorily dispersed across the surface. Lumina decrease in width toward the apertures. Simplicolumellate muri are 0.5 wide. Tricolpate. Simple colpi with acute ends, about 23 to 30 µm in length, and 5 to 8 µm wide. Small apocolpium zone.

Remarks. Medium size. Reticulate. Heterobrochate. Decreasing pattern of columellae toward the apertures and the equator. Tricolpate. Small apocolpium zone.

Species.Dichondra microcalyx (Hallier f.) Fabris (Plate 11, figures 31–35)

Description. Monad, radially symmetrical, isopolar, subtriangular to circular amb, elliptical truncate outline in equatorial view, prolate shape. Medium size (25–35 µm). Tectate perforate exine, 2 to 2.2 µm thick. Visible and well-defined nexine (0.5 m). Tectum 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm high. Foveoreticulate. Heterobrochate. Circular lumina 0.5 to 1 µm in diameter. Smaller ones located at the apocolpium zone; larger lumina at the mesocolpium zone. Tricolpate. Marginate colpi with rounded ends, about 3 to 5 µm wide and 22 to 33 µm long. Wide apocolpium zone.

Remarks. Medium size. Subtriangular to circular amb, elliptical truncate outline in equatorial view, prolate shape. Foveoreticulate. Heterobrochate. Visible nexine thicker than the tectum. Ornamentation pattern. Tricolpate.

Species.Evolvulus villosus Ruiz & Pav. (Plate 11, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (30–37 µm). Tectate perforate exine about 2 µm thick. Visible and well-defined nexine. Tectum 0.3 to 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Columellae slightly decrease in size toward the aperture. Foveolate. Circular foveolae about 0.5 µm in diameter. Foveolae become slightly denser toward the apertures. Pantocolpate (12–15 apertures). Simple brevicolpi with acute ends, about 7 to 10 µm long and 2 µm wide, arranged in groups of five with an H-like pattern.

Remarks. Medium size. Apolar. Foveolate. Pantocolpate (12–15 apertures), with simple brevicolpi arranged in groups of five with the exine depressing close the apertures.

Species.Ipomoea dumetorum Willd. (Plate 12, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Medium to very large size (85–105 µm). Semitectate exine, 6.5 to 7 µm thick. Very thick nexine (5.7 to 6 µm). Tectum 0.3 to 0.5 µm thick. Conspicuous columellae 0.5 µm high. Echinate–reticulate. Large conical echinae 8 to 12 µm high, are wider at the base (3 to 4 µm), thinning toward the tip (2 µm). Six of the larger echinae are arranged hexagonally around the aperture. Smaller echinae (1 to 1.5 µm high) are present between the larger ones, delimiting a hexagonal lumen (lophate) 16 to 20 µm wide. Simplicolumellate muri 2.5 µm wide. Pantoporate (about 50 pores). Simple circular pores 5 µm in diameter. There is one pore per lumen (metareticulate).

Remarks. Very large size. Thick nexine. Complex echinate-reticulate ornamentation (Lophate, metareticulate). Echinae arranged in a hexagonal shape forming a wide lumen around the aperture. Pantoporate (about 50 pores).

Species.Jacquemontia unilateralis (Roem. & Schult.) O'Donell (Plate 12, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Large size (48–55 µm). Eutectate exine, about 3.5 to 4 µm thick, thinning toward the aperture (2 µm). Visible nexine. Tectum about 0.6 to 0.7 µm thick. Digitate columellae 2 to 2.5 µm high, branched into 2 to 3 arms. Microechinate. Microechinae 0.5 µm or less. Microechinae probably correspond with the columellae’s capita. Pantocolpate (12 brevicolpi). Simple brevicolpi are about 10 µm long and 3 to 4 µm wide. Brevicolpi with rounded ends, disposed in groups of five forming an H-like shape.

Remarks. Large size. Digitate columellae with projections above tectum (Microechinae). As in Evolvulus, brevicolpi are arranged in an H-like pattern but differ in the shape of the aperture’s ends.

CUCURBITACEAE Juss.

Species.Cucumis sativus L. (Plate 12, figures 11–15)

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical to elliptical acuminate outline in equatorial view, spheroidal to oblate shape. Medium to large size (40–60 µm). Tectate perforate exine, 2 to 2.5 µm thick. Visible thick nexine (0.7 µm). Tectum 0.5 to 0.7 µm thick and conspicuous columellae, about 1 to 1.2 µm high. Microreticulate. Small circular lumina less than 0.5 µm in diameter, densely dispersed across the surface. Triporate. Annulate circular ectopore, 10 to 13 µm in diameter. Costate circular endopores of similar size. Costae are considerably thick. Exine separates toward the apertures, forming vestibula 1.2 to 1.5 µm high.

Remarks. Medium to large size. Thick nexine. Densely microreticulate ornamentation, presence of a thick costa and a conspicuous vestibulate condition. Triporate.

Species.Cyclanthera mathewsii Arn. ex A.Gray (Plate 12, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, hexagonal amb, elliptical acuminate outline in equatorial view, oblate shape. Medium size (42–50 µm). Semitectate exine, about 4 to 4.2 µm. Visible nexine (1 to 1.2 µm thick). Tectum 1 µm thick. Conspicuous columellae 2 µm high. Columellae decrease in size toward the apertures. Exine with a crescentic pattern. Fossulate. Irregular fossulae. Larger fossulae (about 4 µm) are predominant at the apocolpium and mesocolpium zones. Fossulae strongly decrease in size toward the aperture margin and less sharply to the aperture ends. Stephanocolporate (five apertures). Marginate ectocolpi 43 to 50 µm long and 2 to 6 µm wide. Ectocolpi with acute ends. Costate lalongate endopores, about 4 to 5 µm high and 8 to 10 µm wide. Costae, about 1.5 to 2 µm thick. Exine separates close the apertures, forming fastigia 1.5 µm high. Medium-sized apocolpium zone. Difficult to observe in equatorial view.

Remarks. Large size. Hexagonal amb. Exine with a crescentic pattern. Fossulae’s pattern. Stephanocolporate (five apertures). Endopores with thick costae and conspicuous fastigia.

Species.Sicyos baderoa Hook. & Arn. (Plate 12, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, oblate shape. Large size (60–86 µm). Intectate exine, 1.5 to 1.7 µm thick. Visible nexine (0.5 to 0.7 µm thick). Echinate and locally granulate at the apertures’ margin. Conical echinae are 4 to 6 µm high, slightly wider at the base, separated by 1 to 3 µm. Echinae distribution has an irregular pattern. Stephanocolpate (eight apertures). Marginate irregular colpi with rounded ends, about 36 to 60 µm long and 8 to 12 µm wide. Presence of an ornamented aperture membrane. Medium-sized apocolpium zone.

Remarks. Large size with thin exine. Stephanocolpate (eight apertures), echinate and locally granulate (at colpi). Presence of an ornamented aperture membrane.

CYPERACEAE Juss.

Species.Cyperus laxus Lam. (Plate 12, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, asymmetrical, heteropolar, sub-circular to quadrangular amb, square-like shape. Small size (22–27 µm). Tectate perforate exine, about 1 µm thick. Slightly visible thin nexine. Tectum about 0.2 µm thick and conspicuous columellae 0.5 µm high. Exine becomes slightly thinner reaching the aperture zone. Punctate to microreticulate. Circular puncta/lumina less than 0.5 µm in diameter. Pantocolpate. (4–5 colpi). Simple irregular (pseudo)apertures 3 to 5 µm long and 3 to 3.5 µm wide.

Remarks. Small size. Dense punctate to microreticulate ornamentation. Pantocolpate. (4–5 colpi).

Species.Cyperus odoratus L. (ex-Torulinium odoratum (L.) S.S.Hooper) (Plate 12, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, asymmetrical, apolar to heteropolar, sub-triangular amb, square-like shape. Small to medium size (20–27 µm). Tectate perforate exine 1.2 to 1.5 µm thick. Visible nexine. Tectum about 0.3 to 0.5 µm thick. Slightly conspicuous columellae 0.5 µm high. Punctate. Very small puncta, less than 0.5 µm in diameter. Pantoporate (3–4 pores). Simple circular and operculate(?) (pseudo)apertures 3 to 5 µm in diameter. Presence of aperture membranes with granulate ornamentation. The (pseudo)apertures are distributed as in a ‘pantoaperturate’ condition.

Remarks. Small size. Punctate. (Pseudo)apertures with pantoporate condition and presence of granulate aperture membranes. The (pseudo)apertures are distributed resembling a ‘pantoaperturate’ condition.

EUPHORBIACEAE Juss.

Species.Euphorbia serpens Kunth (ex-Chamaesyce serpens (Kunth) Small) (Plate 12, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical acuminate outline in equatorial view, prolate shape. Medium size (25–32 µm). Tectate perforate exine about 2 to 2.2 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm high, increasing in height toward the equator (crescentic pattern). Fossureticulate. Circular to irregular lumina 0.5 to 1 µm wide, heterogeneously dispersed across the surface. Tricolporate. Planaperturate. Marginate ectocolpi with rounded ends, about 20 to 27 µm long and 2 to 4 µm wide. Visible margo 1 to 1.5 µm wide. Costate lalongate endopores 2 to 4 µm high and 7 to 10 µm wide. Projected mesocolpium. Large apocolpium zone.

Remarks. Medium size. Fossureticulate with crescentic pattern. Circular and irregular lumina across the surface. Tricolporate. Planaperturate. Projected mesocolpium gaves the grain the subtriangular amb. Ectocolpi with wide margo and costate endopores.

Species.Croton alnifolius Lam. (Plate 13, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Large size (50–58 µm). Intectate exine 1 to 1.2 µm thick. Visible thin nexine about 0.5 µm thick. Inconspicuous capitate columellae. Gemmate to clavate. Triangular gemmae are about 1.2 to 1.5 µm high and 1.5 µm wide. Pluricolumellate gemmae to clavae-like structures form groups of five to six in a ring-like conformation (Croton pattern). Inaperturate. Exine surface with few and small weakening zones.

Remarks. Large size. Inaperturate. Croton pattern. Pluricolumellate gemmae to clavae-like structures. In contrast to Jatropha, this grain is smaller.

Species.Euphorbia peplus L. (Plate 13, figures 6–10)

Description. Monad, radially symmetrical, ispolar, circular to subtriangular amb, circular outline in equatorial view, oblate spheroidal shape. Medium size (25–32 µm). Semitectate exine 2 µm thick. Visible nexine. Tectum is 0.5 µm thick. Conspicuous columellae 1 µm high. Collumelae decrease gradually in size toward the apertures and the apocolpium zone. Reticulate. Heterobrochate. Irregular lumina 1 to 1.5 µm wide aleatorily dispersed across the surface, decreasing in size toward the apertures. Tricolporate. Marginate ectocolpi about 23 to 30 µm long and 5 to 7 µm wide, narrowing toward the apocolpium zone. Ectocolpi with rounded ends, narrowing at the central part. Simple lalongate endopores 4 µm high and 7 to 8 µm wide. In the equatorial view the grain is geniculate, forming a bulge related to the ectoaperture. Exine separates toward the aperture, forming a small fastigium (0.5 µm). Medium-sized apocolpium zone.

Remarks. Medium size. Reticulate. Heterobrochate. Ornamentation pattern (change in lumen width). Tricolporate. Marginate ectocolpi. Geniculate in equatorial view.

Species.Jatropha macrantha Müll.Arg. (Plate 13, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb, spheroidal shape. Large size (93–100 µm). Intectate exine about 1 to 1.2 µm thick. Visible thin nexine about 0.5 µm thick. Inconspicuous columellae. Gemmate. Pluricolumellate gemmae-like structures about 2 to 2.3 µm high form groups of five to six in a ring-like conformation (Croton pattern). Triangular elements vary from 2 to 3 µm wide. Inaperturate. Exine surface with pronounced weakening zones.

Remarks. Large size. Gemmate. Pluricolumellate gemmae-like structures. Inaperturate. Thicker exine and wider exine weakening zones than in Croton.

FABACEAE Lindl.

Species.Hoffmannseggia miranda Sandwith (Plate 13, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, obtuse convex amb, ellipsoidal outline in equatorial view, prolate spheroidal shape. Large size (50–70 µm). Semitectate exine 3.5 to 4 µm thick. Visible nexine, slightly decreasing in thickness toward the apertures. Tectum 0.5 µm. Conspicuous uniform columellae 2 to 2.5 µm high. Reticulate. Homobrochate. Circular to irregular lumina 1 to 1.2 µm in width. Simplicolumellate, well-developed muri 0.5 µm wide. Tricolporate. Strongly marginate ectocolpi 48 to 65 µm long and 10 to 12 µm wide. Margo is 1.5 to 1.7 µm wide. In polar view, two bulges delimit the ectocolpi. Costate projected circular endopores 7 to 9 µm in diameter. Medium-sized to small apocolpium. Difficult to find in equatorial view.

Remarks. Large size. Thick exine. Reticulate. Homobrochate. Tricolporate. In polar view two bulges delimit the ectocolpi, producing a very characteristic pattern around the apertures. Strongly marginate ectoaperture.

Species.Mimosa albida Humb. & Bonpl. ex Willd. (Plate 13, figures 21–25)

Description. Tetrahedral tetrad of very small size (7–10 µm). Pollen grains with radially symmetrical, isopolar, circular amb. Very small pollen grains (less than 5 µm). Eutectate exine 0.5 to 0.6 µm thick. Nexine not visible. Inconspicuous tectum and columellae. Psilate. Inaperturate.

Remarks. Dispersal unit. Small size of the tetrad and pollen grains. Inaperturate. Psilate grains.

Species.Neltuma juliflora (Sw.) Raf. (ex-Prosopis juliflora) (Plate 13, figures 26–30)

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical emarginate outline in equatorial view, peroblate shape. Medium size (30–37 µm). Tectate perforate exine 1.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Inconspicuous columellae less than 0.5 µm high. Sexine decreases in thickness toward the apertures. Punctate to microreticulate. Small circular lumina less than 0.5 µm in diameter widely dispersed across the surface. Tricolporate. Marginate ectocolpi with rounded ends, about 30 to 35 µm long and 5 to 6 µm wide. Simple circular (8 µm in diameter) to slightly lalongate endopores (6 µm high and 8 µm wide). Exine separates toward the aperture, forming small fastigia. Reduced apocolpium zone. Difficult to find in equatorial view.

Remarks. Medium size. Elliptical emarginate outline. Inconspicuous columellae. Tricolporate. Fastigiate. Puncate to microreticulate.

Species.Parkinsonia aculeata L. (Plate 13, figures 31–35)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate shape. Medium size (30–35 µm). Semitectate exine 1.5 to 2 µm thick. Visible thin nexine. Tectum 0.3 to 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm high. Collumelae sharply decrease in size toward the apertures and slightly toward the apocolpium zone. Reticulate. Heterobrochate. Larger pentagonal lumina are 1 to 1.5 µm wide, distributed across the intercolpium zones. Smaller lumina are located next to the aperture (0.5 µm wide or less). At the apocolpium, the reductional pattern of lumen size forms a well-defined triangular zone. Simplicolumellate muri 0.5 µm wide. Tricolporate. Strongly marginate ectocolpi 23 to 28 µm long and 2 to 8 µm wide, with rounded ends. Indistinct endopores about 4 to 5 µm high and 2 to 3 µm wide. Aperture membrane is psilate and associated with the endopores. Endopores are difficult to observe in equatorial view. Medium-sized apocolpium.

Remarks. Medium size. Reticulate. Heterobrochate. Larger pentagonal lumina at intercolpium zones. Tricolporate. Aperture membrane.

Species.Senna birostris (Dombey ex Vogel) H.S.Irwin & Barneby (Plate 13, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, heteropolar, subtriangular amb, ellipsoidal or obtuse outline in equatorial view, oblate shape. Medium size (33–40 µm). Tectate perforate exine 1.5 µm thick. Visible thin nexine, decreasing in thickness at the mesocolpium zone. Tectum 0.3 µm thick. Columellae 0.5 µm high. Microreticulate. Irregular lumina 0.5 to 0.7 µm wide, homogeneously dispersed across the surface. Tricolporate to syncolporate at only one pole. Marginate ectocolpi with rounded ends about 36 to 40 µm long and 4 to 8 µm wide. Costate lalongate projected endopores 4 to 6 µm high and 10 to 12 µm wide. Geniculate in equatorial view.

Remarks. Medium size. Heteropolar. Microreticulate ornamentation. Syncolporate at only one pole. Projected endopores.

Species.Tara spinosa (Molina) Britton & Rose (ex- Caesalpinia spinosa) (Plate 14, figures 1–5)

Description. Monad, radially symmetrical, isopolar, circular amb, circular to elliptical outline in equatorial view, oblate spheroidal shape. Medium size (40–50 µm). Semitectate exine 3 to 3.5 µm. Visible nexine (1 to 1.5 µm), thicker than tectum (0.5 to 0.8 µm). Conspicuous columellae 1 to 1.2 µm high, increasing in size toward the apertures. Reticulate-fossulate. Reticulum present at the intercolpium. Heterobrochate with irregular lumina shapes. Larger lumina 1 to 1.7 µm distributed across the intercolpium but decreasing toward the apocolpium. Simplicolumellate muri are about 0.5 to 0.7 µm wide. Fossulate at margo’s surface, with fossulae 0.7 to 1 µm, close to the apertures. Tricolporate. Marginate ectocolpi with rounded ends, about 38 to 45 µm long and 9 to 10 µm wide. Ectocolpi with well-developed margo (1.5 µm). In polar view, two small bulges delimit the ectocolpi. Simple lolongate endopores 9 to 13 µm high and 3 to 5 µm wide.

Remarks. Medium size. Reticulate-fossulate. Tricolporate. Simple lolongate endospores. Morphologically similar to Hoffmannseggia, differing in size, exine thickness and ornamentation pattern.

Species.Trifolium repens L. (Plate 14, figures 6–10)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate spheroidal shape. Medium size (25–30 µm). Semitectate exine 1.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Slightly conspicuous columellae 0.5 µm high, decreasing in size toward the aperture. Reticulate. Heterobrochate. Irregular lumina 0.7 to 1.2 µm wide, dispersed aleatorily across the surface. Simplicolumellate muri 0.5 µm wide. Tricolporate. Marginate ectocolpi with acute ends, about 20 to 27 µm long and 2 to 5 µm wide. Margo 2 to 2.5 µm wide, with psilate ornamentation. Costate lalongate endopores 4 to 5 µm high and 5 to 8 µm wide. Wide open endopores. Difficult to find in polar view.

Remarks. Medium size. Prolate spheroidal shape. Reticulate. Heterobrochate, simplicolumellate muri. Tricolporate. The aperture features include a wide psilate margo.

Species.Vachellia macracantha (Humb. & Bonpl. ex Willd.) Seigler & Ebinger (Plate 14, figures 11–15)

Description. Polyad of large size (60–80 µm). Pollen grains radially symmetrical, apolar, quadrangular amb. Medium-sized pollen grain (23–30 µm). Polyad is composed of 16 units (eight at the center and eight laterally arranged). Tectate perforate exine 1 to 1.5 µm. Visible nexine. Tectum is 0.5 µm thick. Slightly conspicuous columellae 0.5 µm. Punctate to scabrate. Circular puncta less than 0.5 µm in diameter spread across the surface. In the polyad’s polar view, dense scabrae can be observed. Inaperturate. Difficult to find in equatorial view.

Remarks. Dispersal unit. Large size polyad. Medium-sized pollen units. Ornamentation pattern of individual grains is punctate to scabrate. Inaperturate grains.

FRANKENIACEAE Desv.

Species.Frankenia chilensis C.Presl ex Schult. & Schult.f. (Plate 14, figures 16–20)

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, spheroidal shape. Large size (53–60 µm). Eutectate exine 1.5 to 2 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 0.8 to 1 µm high. Columellae’s capita surpass the tectum layer, giving the appearance of microechinae. Gemmate to slightly clavate. Small gemmae/clavae, less than 1 µm high, about 1 to 1.2 µm wide, are located at the apocolpium zone. Gemmae/clavae decrease in width toward the mesocolpium zone and the apertures. Tricolpate. Simple irregular colpi with rounded ends and membranous structure, about 50 to 57 µm long and 10 to 13 µm wide. Colpi membrane is granulate.

Remarks. Large size. Gemmate to slightly clavate. Tricolpate. Ornamented aperture membrane.

GERANIACEAE Juss.

Species.Erodium cicutarium (L.) L'Hér. (Plate 14, figures 21–25)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, oblate spheroidal shape. Large size (50–60 µm). Semitectate exine 5 to 5.5 µm thick. Visible thick nexine (1 to 1.5 µm). Tectum 1 µm thick. Conspicuous columellae 3 µm. Striato-reticulate (heterobrochate). Striae are cross-linked, forming reticulae in the grooves. Lumen size is variable, about 1 to 2 µm, and the muri (striae) thickness is about 1.2 µm. Striae become denser at the apocolpium zone; decreasing lumen size. Tricolporate. Simple brevicolpi with rounded ends, about 13 to 15 µm long and 5 to 8 µm wide. Simple circular endopores 4 to 5 µm in diameter. Large apocolpium zone. Endoapertures difficult to observe in equatorial view.

Remarks. Large size. Striato-reticulate. Heterobrochate. Brevicolpate. Slightly inconspicuous endopores.

Species.Geranium limae R.Knuth (Plate 14, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, oblate shape. Large size (53–68 µm) Semitectate exine 7 µm thick. Visible nexine (2 µm thick). Tectum 2 µm thick. Conspicuous columellae 3 µm high. Columellae’s capita are notably wide. Reticulate, homobrochate. Pentagonally shaped lumina 2 µm in width. Simplicolumellate muri 1 µm in thickness. Lumina are delimited by 5–6 columellae. Tricolporate to stephanocolporate (four colpori). Simple irregular brevicolpi with acute ends, about 15 to 20 µm long and 7 to 8 µm wide. Simple circular to slightly lalongate endopores 4 to 5 µm in diameter. Large apocolpium zone. Endoapertures difficult to observe in equatorial view.

Remarks. Large size. Thick exine. Reticulate, pentagonally shaped lumina. Tricolporate to stephanocolporate (four colpori). Brevicolpate.

HELIOTROPIACEAE Schrader, nom. cons.

Species.Heliotropium arborescens L. (Plate 14, figures 30–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical truncate outline in equatorial view, oblate spheroidal shape. Small to medium size (20–26 µm). Eutectate exine 1.5 µm thick. Visible nexine. Tectum 0.3 to 0.5 µm thick. Inconspicuous columellae. Exine increases in thickness toward the apocolpium zone and colpori. Psilate. Heterocolpate (3 colpori + 3 colpi). Simple ectocolpi 18 to 23 µm long and 3 to 5 µm wide. Colpori have acute ends, while colpi have rounded ends. Costate circular to slightly lalongate endopores 5 to 8 µm wide. Reduced apocolpium zone. Exine separates toward the apertures, forming fastigia 1.5 µm high.

Remarks. Small to medium size. Heterocolpate. Presence of fastigia. Psilate. Exine with variable thickness, with inconspicuous columellae.

KRAMERIACEAE Dumort.

Species.Krameria lappacea (Dombey) Burdet & B.B.Simpson (Plate 14, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, circular outline in equatorial view, spheroidal shape. Medium size (40–45 µm). Eutectate exine 1.5 to 2 µm thick. Visible nexine (1.2 µm thick). Tectum less than 0.5 µm thick. Slightly conspicuous columellae 0.5 µm high. Striate. Striae about 0.7 µm wide, larger than the grain itself, covering the intercolpium zone. Striae merge with each other at the apocolpium zone but become parallel to each other at the equator. Tricolporate. Simple ectocolpi with acute ends, about 38 to 42 µm long and 5 to 8 µm wide. Psilate aperture membrane. Costate lalongate endopores 5 µm high and 10 to 12 µm wide. Endopores are wide, almost forming a cingulum. Large apocolpium zone. The exine separates toward the apertures forming fastigia 1.5 µm high.

Remarks. Medium size. Striate. Striae merge at the apocolpium zone but run parallel at the equator. Tricolporate. Wide endopores, almost endocingulate. Fastigiate.

LAMIACEAE Martinov

Species.Hyptis uncinata Benth. (Plate 15, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, elliptical amb, rectangular obtuse outline in equatorial view, oblate shape. Medium size (25–38 µm). Semitectate exine 2 µm thick. Visible nexine (0.5 µm thick). Tectum 0.3 to 0.5 µm. Conspicuous columellae 1 to 1.2 µm high. Columellae strongly decrease in size toward the apertures. Reticulate. Homobrochate. Irregular-shaped lumina 1 to 1.2 µm wide. Simplicolumellate muri 0.7 µm thick. Stephanocolpate (six colpi). Marginate colpi with acute ends, about 20 to 25 µm long and 3 to 5 µm wide. 1.2 to 1.7 µm thick. Margo’s surface is psilate. Colpi and aperture membrane are projected. Medium-sized apocolpium zone.

Remarks. Medium size. Elliptical amb, rectangular obtuse outline in equatorial view. Reticulate. Homobrochate. Irregular shape but constant wide. Stephanocolpate (six colpi). Margo’s surface. Presence of a projected aperture membrane, generating a particular outline in equatorial view.

Species.Lepechinia lamiifolia (Benth.) Epling (Plate 15, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, elliptical amb, elliptical convex outline in equatorial view, oblate spheroidal shape. Medium size (30–42 µm). Semitectate exine 1.5 to 2 µm thick. Visible thin nexine. Tectum 0.3 to 0.5 µm thick. Conspicuous columellae 0.7 to 1 µm high. Columellae slightly decrease in size toward the apertures. Reticulate. Heterobrochate, irregular lumina 1 to 3 µm wide. Larger lumina located at the mesocolpium zone. Simplicolumellate muri 1 µm wide. Stephanocolpate (six colpi). The distribution of colpi may also suggest a ‘trigeminate’ type of aperture (grains with colpi arranged in trios). Long marginate colpi with acute ends, about 27 to 38 µm long and 4 to 5 µm wide. Irregular margo’s surface is psilate to scabrate. Projected margo. Apertures have a mirror rather than symmetrical distribution, having three apertures per meridional face. Small to medium-sized apocolpium.

Remarks. Medium size. Reticulate. Heterobrochate. Ornamentation pattern. Stephanocolpate (six colpi). Apertures have a mirror rather than symmetrical distribution. The distribution of colpi may also suggest a ‘trigeminate’ type of aperture (grains with colpi arranged in trios).

Species.Minthosachys mollis (Benth.) Griseb. (ex-Minthostachys tomentosa) (Plate 15, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, elliptical amb, circular to slightly elliptical outline in equatorial view, oblate spheroidal shape. Small size (22–35 µm). Tectate perforate exine 1.5 to 2 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 0.5 to 0.8 µm high. (Micro)reticulate to fossulate. Heterobrochate. (Micro)reticulate at the mesocolpium zone and fossulate toward the apocolpium zone. Irregular lumina 0.5 to 0.7 µm wide. Small elongated lumina are located at the apocolpium zone, increasing in width toward the mesocolpium zone. Simplicolumellate muri less than 0.5 µm wide. Stephanocolpate (six colpi). Marginate colpi with acute ends, about 18 to 25 µm long and 3 to 5 µm wide. Thin margo. Medium-sized apocolpium zone.

Remarks. Small size. Ornamentation pattern is (micro)reticulate to fossulate. Heterobrochate. Stephanocolpate (six colpi). Thin margo.

Species.Salvia rhombifolia Ruiz & Pav. (Plate 15, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, elliptical amb, elliptical outline in equatorial view, oblate shape. Medium size (32–42 µm). Semitectate exine 1 µm thick. Visible thin nexine. Tectum about 0.2 µm thick. Conspicuous columellae 0.5 µm high. Columellae decrease in size toward the apertures. Reticulate. Heterobrochate. Irregular lumina of variable size. Smallest lumina (0.7 to 1 µm wide) are located at the apocolpium zone, increasing in size toward the mesocolpium zone (3 to 4 µm wide). Smaller lumina also extend to the widest areas between apertures. Simplicolumellate muri 0.5 µm wide. Stephanocolpate (six colpi). The distribution of colpi may also suggest a ‘trigeminate’ type of aperture (grains with colpi arranged in trios). Marginate colpi with acute ends, about 26 to 36 µm long and 3 to 5 µm wide. Granulate margo. Apertures have a mirror rather than symmetrical distribution, having three apertures per meridional face. Small to medium-sized apocolpium.

Remarks. Medium size. Reticulate. Heterobrochate. Stephanocolpate (six colpi). Granulate margo. Apertures have a mirror rather than symmetrical distribution, having three apertures per meridional face.

Species.Stachys peruviana Dombey ex Benth. (Plate 15, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, circular amb, circular outline in equatorial view, oblate spheroidal shape. Small to medium size (22–27 µm). Tectate perforate exine 1 to 1.2 µm thick. Visible thick nexine. Nexine is thicker than sexine. Tectum 0.3 µm thick. Slightly conspicuous columella 0.5 µm high. Sexine decreases in thickness toward the apertures. Microreticulate. Heterobrochate. Irregular lumina less than 1 µm wide. Smaller lumina (less than 0.5 µm), resembling puncta, located at the apocolpium zone and next to the apertures. Lumina increase slightly in size toward the mesocolpium zone. Tricolpate. Marginate colpi with acute ends, about 16 to 22 µm long and 4 to 9 µm. Slightly projected margo with psilate surface, about 0.3 to 0.5 µm. Small apocolpium zone.

Remarks. Small to medium size. Microreticulate. Heterobrochate. Nexine is thicker than sexine. Tricolpate. Marginate colpi. Slightly projected margo with psilate surface.

LOASACEAE Juss.

Species.Loasa nitida Desr. (Plate 15, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, circular amb, elliptical truncate outline in equatorial view, prolate shape. Small size (18–20 µm). Tectate perforate exine 1 to 1.2 µm thick. Visible thin nexine. Nexine produces an internal shadow with a globular shape. Tectum less than 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm in height. Punctate to microreticulate. Circular to irregular lumina less than 0.5 µm wide, dispersed across the surface. Tricolporate. Marginate ectocolpi of acute ends about 15 to 20 µm long and 7 to 8 µm wide. Costate lalongate endopores, about 4 to 5 µm high and 5 to 7 µm wide. Endoapertures are difficult to observe in equatorial view, yet they are very well defined in polar view. Exine separates toward the apertures, forming a well-defined fastigia (1 µm). Reduced apocolpium zone.

Remarks. Small size. Thick exine. Punctate to microreticulate. Tricolporate. Well-defined fastigia. Endoapertures are difficult to observe in equatorial view, yet they are very well defined in polar view.

Species.Nasa urens (Jacq.) Weigend (Plate 15, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, circular amb, elliptical truncate outline in equatorial view, prolate shape. Small to medium size (20–25 µm). Tectate perforate exine 1 to 1.5 µm thick. Slightly visible nexine. Nexine produces an internal shadow with a triangular to hexagonal shape. Tectum 0.3 to 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm high. Sexine decreases toward the apertures. Microreticulate. Homobrochate. Irregular lumina 0.3 to 0.5 µm wide. Simplicolumellate muri less than 0.5 µm wide. Tricolporate. Slightly marginate ectocolpi with acute ends, about 18 to 23 µm long and 5 to 9 µm wide. Costate lalongate endopores 5 to 6 µm high and 8 to 10 µm wide. Endopores are difficult to observe in equatorial view. The exine separates toward the apertures, forming fastigia (1.5 µm). Reduced apocolpium zone.

Remarks. Small to medium size. Microreticulate. Homobrochate. Tricolporate. Reduced apocolpium zone. Well-defined fastigia, wider than in Loasa.

Species.Presliophytum arequipense Weigend (Plate 15, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, subtriangular amb, elliptical acuminate obtuse outline in equatorial view, peroblate shape. Small size (11–17 µm). Eutectate exine 1 µm thick. Nexine not visible. Tectum 0.3 µm thick. Inconspicuous columellae, less than 0.5 µm high. Exine decreases toward the aperture. Psilate. Presence of well-developed interloculum. Tricolporate. Simple ectocolpi with rounded ends, about 10 to 16 µm and 5 µm wide. Costate lalongate endopores 2 to 3 µm high and 5 to 7 µm wide. Small apocolpium zone.

Remarks. Small size. Peroblate shape, elliptical acuminate obtuse outline in equatorial view. Psilate ornamentation. Tricolporate. Simple ectocolpi. In contrast to Loasa and Nasa, this genus is not fastigiate. Presence of well-developed interloculum.

MALVACEAE Juss.

Species.Abutilon bivalve (Cav.) Dorr (ex-Bastardia bivalvis) (Plate 16, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, spheroidal shape. Large size (93–100 µm). Tectate perforate exine 2.5 µm thick. However, sexine reaches 4 µm in thickness at zones with supratectal elements. Visible nexine. Tectum is 0.5 µm thick. Conspicuous columellae 1.3 µm high, but increasing toward the position of supratectal elements, being about 2 µm high. Echinate and punctate. Conical to hook-like echinae 5 to 6 µm high, Pluricolumellate. Echinae supported by 4 or 5 μm columellae at the base. The space between echinae is densely punctate. Circular to irregular puncta less than 0.5 µm in diameter. Tricolporate. Simple brevicolpi with acute ends, about 10 to 13 µm long and 5 µm wide. Ectocolpi are difficult to observe. Costate circular endopores, about 8 to 10 µm in diameter. Difficult to find a perfect polar or equatorial view. Exine with a weakening zone with a groove-like appearance.

Remarks. Large size. Echinate and punctate. Conical to hook-like echinae. Tricolporate. Inconspicuous brevicolpi. Costate endopores.

Species.Cristaria multifida (Dombey ex Cav.) Cav. (Plate 16, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, apolar, circular amb, circular outline in equatorial view, spheroidal shape. Large size (55–63 µm). Semitectate exine 2 µm thick but reaching 4 µm below supratectal elements. Visible thick nexine (1 µm). Tectum 0.3 to 1 µm thick. Conspicuous columellae 0.7 to 2 µm high, increasing in size toward supratectal elements. Echinate and foveoreticulate. Conical echinae 4 to 5 µm high, wider at the base (2 µm) and thinning toward the tip. Pluricolumellate echinae, supported by 6–7 columellae. Circular to irregular lumina 0.7 µm to 1.2 µm wide. Negative reticulum. Tricolporate. Simple brevicolpi with acute ends 8 to 10 µm long and 2 to 3 µm wide. Inconspicuous ectocolpi. Costate circular endopores 6 to 8 µm in diameter. Difficult to find a perfect polar or equatorial view. Exine with a weakening zone with a groove-like appearance.

Remarks. Smaller in size in comparison to Abutilon. Ornamentation pattern (Echinate and foveoreticulate). Inconspicuous brevicolpi. Costate endopores. Exine with a weakening zone with a groove-like appearance.

Species.Fuertesimalva chilensis (A.Braun & C.D.Bouché) Fryxell (Plate 16, figures 11–15)

Description. Monad, radially symmetrical, apolar, circular amb. Large size (58–65 µm). Tectate perforate exine 2.5 µm thick but thickening (3.5 µm) below supratectal elements. Visible well-defined nexine (1.5 µm thick). Tectum 0.5 µm thick. Conspicuous columellae 0.5 to 1.5 µm high. Sexine increases in thickness below supratectal elements. Echinate and punctate. Acicular echinae 4 to 5 µm high and slightly wider at the base. Pluricolumellate echinae, supported by 3–4 columellae. Irregular puncta less than 0.5 µm wide. Puncta are densely dispersed across the surface. Some puncta are elongated, resembling a fossulae. Pantocolporate (nine colpori). Simple constricted ectobrevicolpi with acute ends, about 6 to 9 µm long and 2 µm wide. Costate circular endopores 4 to 5 µm in diameter. Difficult to find a perfect polar or equatorial view. Exine with a weakening zone with a groove-like appearance.

Remarks. Large size. Echinate and punctate. Acicular echinae. Pantocolporate (nine colpori). Inconspicuous brevicolpi. Costate endopores. Exine with a weakening zone with a groove-like appearance.

Species.Gaya atiquipana Krapov. (Plate 16, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for the region of Arequipa, Peru–

Description. Monad, radially symmetrical, apolar, circular amb. Large size (95–107 µm). Tectate perforate exine 3 µm thick, in but thickening (6 µm) below supratectal elements. Visible nexine (1 µm thick). Tectum 0.5 µm thick. Conspicuous columellae 1.5 to 4.5 µm high. Columellae increase in size below supratectal elements. Echinate and punctate. Conical to slightly acicular echinae 5 to 6 µm, wider at the base (1.5 µm), thinning toward the tip. Echinae with a well-developed base. Pluricolumellate. Echina is supported by columellae that are 5 to 6 μm height. Irregular puncta 0.5 to 0.7 µm wide, dispersed across the surface. Pantocolporate (12 colpori). Simple ectobrevicolpi with acute ends about 10 to 12 µm long and 3 to 4 µm wide. Brevicolpi are difficult to observe. Costate circular endopore width is about 7 to 12 µm in diameter, endopores separated from each other by distance of 7 to 10 µm. Exine with a weakening zone with a groove-like appearance.

Remarks. Large size. Echinate and punctate. Echinae with a well-developed base. Exine under echinae becomes thicker. Pantocolporate (12 colpori).

Species.Malva parviflora L. (Plate 16, figures 21–25)

Description. Monad, radially symmetrical, apolar, circular amb. Large size (90–100 µm). Tectate perforate exine 5 µm thick. Visible and well-developed nexine (4 µm thick). Tectum 0.5 µm thick. Conspicuous columellae 0.5 µm high. Columellae slightly increase in size below supratectal elements. Echinate and punctate. Conical echinae of two sizes. Larger ones 5 to 6 µm high. Slightly wider at the base. Smaller ones 1 µm high, sparsely dispersed. The largest echinae are pluricolumellate, supported by many columellae (indistinct number). Circular puncta less than 0.5 µm in diameter, densely dispersed across the surface. Pantoporate (30 to 40 pores). Simple circular ectopores 3 to 4 µm in diameter. Costate circular endopores 3 to 4 µm in diameter.

Remarks. Very large size. Thick nexine. Sexine pattern. Echinate and punctate with conical echinae of two different sizes. Aperture number (30 to 40 pores).

Species.Melochia pyramidata L. (Plate 16, figures 25–30)

–Members of this genus present heterostyly in their flowers and pollen dimorphism. Two existing pollen morphotypes are described for the genus–

Description (1) Monad, radially symmetrical, isopolar, subtriangular amb, elliptical truncate outline in equatorial view, prolate spheroidal to oblate spheroidal shape. Medium size (30–35 µm). Semitectate exine 1.5 µm thick. Visible nexine. Tectum 0.3 µm thick. Conspicuous columellae 0.7 µm high. Columellae slightly decrease toward the apertures. Reticulate. Heterobrochate. Irregular lumina 0.7 to 1.5 µm wide. Larger lumina are located at the apocolpium zone, sharply decreasing to the mesocolpim zone. Simplicolumellate muri 0.3 to 0.5 µm wide. Tricolporate. Marginate ectocolpi with rounded ends, about 18 to 22 µm long and 2 to 8 µm wide in polar view. Colpi seem to be constricted in equatorial view (2 µm). Costate lalongate endopores 3 to 5 µm high and 8 to 10 µm wide. Exine separates toward the apertures forming fastigia (0.8 to 1 µm high). Medium to small apocolpium zone.

Remarks. Medium size. Variable shape (prolate spheroidal to oblate spheroidal). Reticulate, heterobrochate. Tricolporate. Fastigiate. Medium to small apocolpium zone.

Description (2). Monad, radially symmetrical, isopolar, circular to slightly subtriangular amb, circular to elliptical truncate or acuminate outline in equatorial view, spheroidal to oblate. Medium to large size (45–60 µm). Tectate perforate exine 2 to 2.2 µm thick. Visible nexine (1 µm). Tectum less than 0.5 µm thick. Slightly conspicuous columellae, about 0.7 to 1 µm. Sexine decreases toward the apertures. Microechinate and punctate. Small conical microechinae 0.5 µm high or less, densely dispersed across the surface. Circular puncta about 0.3 to 0.7 µm in diameter, widely dispersed. Tricolporate. Simple irregular breviectocolpi with acute ends, about 20 to 22 µm long and 3 to 5 µm wide in polar view. Brevicolpi seem to be constricted, about 1.5 to 2 µm wide in equatorial view. Costate lalongate endopores 4 µm in height and 8 to 10 µm in width. Endopores have a well-defined rectangular shape. Exine separates toward the apertures forming fastigia (0.5 µm high).

Remarks. Medium to large size. Variable shape (circular to elliptical truncate or acuminate). Microechinate and punctate. Tricolporate. Brevicolpate. Rectangular lalongate endopores. Fastigiate.

Species.Palaua rhombifolia Graham (Plate 16, figures 31–35)

Description. Monad, radially symmetrical, apolar, amb circular. Medium size (40 to 45 µm). Tectate perforate exine 2 µm thick but thickening (3.5 µm) below supratectal elements. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 0.7 to 2 µm high, increasing in size below supratectal elements. Echinate and punctate. Conical to acicular echinae 3 to 3.5 µm high, slightly wider at the base (2 µm). Pluricolumellate echinae, supported by 5–6 columellae. Circular puncta 0.5 to 0.7 µm in diameter, widely dispersed across the surface. Pantocolporate (5–7 colpori). Simple small brevicolpi with acute ends, about 3 to 4 µm long and 1 to 2 µm wide. Costate circular endpores 3 to 6 µm in diameter. Colpori are notably separated (about 10 to 20 µm). Exine with a weakening zone with a groove-like appearance.

Remarks. Medium size. Echinate and punctate. Pantocolporate (5–7 colpori). Brevicolpi. Conical to acicular echinae. Exine with a weakening zone with a groove-like appearance.

Species.Sida acuta Burm.f. (Plate 16, figures 36–40).

Description. Monad, radially symmetrical, apolar, circular amb. Large size (60–65 µm). Tectate perforate exine 2.5 µm thick, thickening (4 µm) below supratectal elements. Visible thick nexine (1.5 µm). Tectum 0.5 µm thick, conspicuous columellae 0.5 µm high but increasing in size (2 µm) below supratectal elements. Echinate and punctate. Densely distributed echinae. Hook-like to slightly acicular echinae 4 to 5 µm high, wide at the base (3 µm). Pluricolumellate echinae, supported by 4–5 columellae. Circular puncta 0.5 µm in diameter, densely dispersed across the surface. Pantoporate (5–7 pores). Simple circular ectopores 4 to 5 µm in diameter. Costate circular endopores 4 to 5 µm in diameter. Pores are separated by 10 to 15 µm.

Remarks. Large size. Echinate and punctate. Hook-like to acicular echinae. Pantoporate (5–7 pores). Densely distributed echinae.

Species.Fuertesimalva peruviana (L.) Fryxell (ex-Urocarpidium peruvianum (L.) Krapov.) (Plate 17, figures 1–5)

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (45–50 µm). Tectate perforate exine 3.5 µm, thickening (4 µm) below supratectal elements. Visible nexine. Sexine thicker than nexine. Tectum 0.5 µm thick. Conspicuous columellae about 2 µm high, increasing in size below supratectal elements (2.5 µm). Echinate and punctate. Conical echinae 3 to 3.5 µm high, wider at the base (2 µm). Pluricolumellate echinae, supported by 5–6 columellae. Circular puncta 0.5 µm in diameter, densely dispersed across the surface. Pantocolporate (at least five colpori). Simple brevicolpi with acute ends, about 3 to 4 µm long and 2 µm wide. Ectocolpi are difficult to observe. Costate circular endopores, about 3 to 5 µm in diameter. Apertures are distinctly separated from each other, about 25 to 30 µm.

Remarks. Medium size. Echinate and punctate. Pantocolporate (at least five colpori). Brevicolporate. Apertures are notably separated.

Species.Waltheria ovata Cav. (Plate 17, figures 6–10)

–Members of this genus present heterostyly in their flowers and pollen dimorphism. Two existing pollen morphotypes are described for the genus–

Description (1). Monad, radially symmetrical, isopolar, quadrangular amb, elliptical truncate to acuminate outline in equatorial view, oblate spheroidal to prolate shape. Medium size (32–40 µm). Semitectate exine 1.5 to 2 µm thick. Visible nexine. Tectum 0.3 to 0.5 µm thick. Conspicuous capitate columellae 0.7 to 1 µm high. Reticulate. Heterobrochate. Irregular to square-like lumina 1 to 2 µm wide. Larger lumina are located at the apocolpium zone, decreasing in size toward the mesocolpium zone and the apertures. Simplicolumellate muri 0.5 to 0.7 µm. Stephanocolporate (four colpori). Marginate ectocolpi with acute ends, about 20 to 25 µm long and 3 to 5 µm wide in polar view. Ectocolpi are slightly constricted (1 to 2 µm wide) at the equator. Costate lalongate endopores 4 µm high and 7 to 8 µm wide. Exine separates in two layers toward the apertures, forming fastigia 0.3 to 0.5 µm high. Wide apocolpium zone.

Remarks. Medium size. Quadrangular amb. Variable outline in equatorial view. Reticula pattern with visible capita. Stephanocolporate (four colpori). Marginate ectocolpi. Fastigiate.

Description (2) Monad, radially symmetrical, isopolar, circular amb, elliptical acuminate outline in equatorial view, prolate shape. Medium size (43–55 µm). Tectate perforate exine 2 µm thick. Visible nexine, decreasing in thickness toward the apertures. Tectum 0.3 µm thick. Slightly conspicuous columellae 1 µm high. Microechinate and punctate. Small conical microechinae 0.3 to 0.5 µm high, sparsely distributed across the surface. Circular puncta 0.5 µm in diameter, densely dispersed across the surface. Stephanocolporate (five colpori). Simple brevicolpi with acute ends, about 18 to 20 µm long and 3 to 4 µm wide. Costate circular endopores 6 to 8 µm in diameter. Exine slightly separates toward the apertures, forming fastigia 0.3 to 0.5 µm high.

Remarks. Medium size. Circular amb, Microechinate and punctate. Stephanocolporate (five colpori). Circular fastigiate endopores.

MONTIACEAE Raf.

Species.Calandrinia alba (Ruiz & Pav.) DC. (Plate 17, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (43–50 µm). Semitectate exine 3 to 3.5 µm. Slightly visible nexine. Tectum 1 µm thick. Conspicuous columellae 1.5 to 2 µm high, decreasing in size toward the apertures. Reticulate. Heterobrochate. Irregular lumina of variable size, about 0.5 to 2.2 µm wide. Lumina heterogeneously dispersed across the surface but decreasing in size toward the apertures. Pantocolpate (10 to 12 colpi). Marginate brevicolpi with acute ends, about 12 to 17 µm long and 2 to 3 µm wide. Operculate brevicolpi. When present, opercula are granulate. Colpi arranged in groups of five, forming an H-like pattern.

Remarks. Medium size. Reticulate. Heterobrochate. Pantocolpate. Aperture arrangement (H-like pattern). Operculate brevicolpi (10 to 12 colpi). When present, opercula are granulate.

Species.Cistanthe calycina (Phil.) Carolin ex Hershk. (Plate 17, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate to elliptical acuminate outline in equatorial view, prolate shape. Medium size (38–45 µm). Semitectate exine 3 µm. Visible and well-defined nexine (1 µm), slightly decreasing toward the apertures. Tectum 1 µm. Conspicuous columellae 1 to 1.2 µm high, rapidly decreasing in size toward the aperture. Foveoreticulate. Circular to irregular lumina 0.5 to 1.5 µm wide. Small circular foveolae are densely located at the mesocolpium zone. Larger foveola are spread at the apocolpium zone, where some of these resemble a fossula-like shape. Tricolpate. Strongly marginate colpi with rounded ends, about 35 to 40 µm long and 8 to 16 µm wide in polar view. Granulate margo. Granulae decrease in size to the outer part of the apertures. Colpi are constricted in equatorial view. Presence of a granulate aperture membrane. Reduced apocolpium zone.

Remarks. Medium size. Variable outline. Columellae rapidly decrease toward the aperture. Foveoreticulate. Tricolpate. Strongly marginate colpi with granulate margo.

MYRTACEAE Juss.

Species.Myrcianthes ferreyrae (McVaugh) McVaugh (Plate 17, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical acuminate outline in equatorial view, oblate shape. Small size (15–22 µm). Eutectate exine 0.7 to 1 µm. Slightly visible nexine, located exclusively at the mesocolpium zone. Tectum 0.3 µm thick. Inconspicuous columellae. Sexine decreases in thickness toward the aperture. Psilate. Tricolporate. Parasyncolporate. Anguloaperturate. Marginate ectocolpi completely fused at the apocolpium zone, about 15 to 22 µm long and 2 to 3 µm wide. Irregular apocolpial field. Costate circular endopores 3 to 5 µm in diameter.

Remarks. Small size. Triangular amb. Elliptical acuminate outline in equatorial view. Triangular amb. Nexine location. Tricolporate. Parasyncolporate. Anguloaperturate. Irregular apocolpial field.

NYCTAGINACEAE Juss.

Species.Boerhavia coccinea Mill. (Plate 17, figures 26–30)

Description. Monad, radially symmetrical, apolar, circular amb. Large size (55–60 µm). Tectate perforate exine 6 µm thick. Visible thick nexine 5 µm. Nexine is thicker than sexine. Tectum 1 µm thick. Slightly conspicuous columellae 1 µm high. Echinate and punctate. Small conical echinae 1.5 to 2 µm high, wider at the base. Echinae are densely distributed. Circular puncta 0.5 to 0.7 µm in diameter, sparsely dispersed across the surface. Pantoporate (about 15 pores). Simple circular ectopores 5 to 6 µm in diameter. Simple circular endopores of same proportions than ectopores.

Remarks. Large size. Thick nexine. Ornamentation pattern is echinate and punctate. Conical echinae. Pantoporate (about 15 pores).

Species.Mirabilis prostrata (Ruiz & Pav.) Heimerl (Plate 17, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Large size (77–82 µm). Tectate perforate exine 6 µm thick. Visible thick nexine (3 µm). Tectum 1 µm thick. Conspicuous columellae 2 µm high. Echinate and punctate. Small acicular echinae 1.5 to 2 µm high, slightly wider at the base. Echinae are densely distributed. Circular puncta 0.5 µm in diameter, sparsely dispersed across the surface. Pantoporate (about 20 pores). Simple circular ectopores 5 to 6 µm in diameter. Costate circular endopores of same proportions than ectopores.

Remarks. Large size. Nexine thick. Ornamentation pattern is echinate and punctate. Acicular echinae, slightly larger than in Boerhavia. Pantoporate (about 20 pores). Costate endopores.

ONAGRACEAE Juss.

Species.Epilobium fragile Sam. (Plate 17, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Tetrahedral tetrad of large size (90–110 µm). Pollen grains with radially symmetrical, triangular amb, elliptical acuminate outline in equatorial view, oblate shape tetrahedral. Large pollen grain (60–67 µm). Eutectate exine 3 µm. Visible thick nexine (1.3 µm). Tectum 1 to 1.2 µm. Slightly conspicuous columellae 0.5 to 0.7 µm high. Sexine increases in thickness toward the apertures (5 to 6 µm). Psilate to slightly scabrate. Triporate. Annulate circular projected ectopores 7 to 10 µm in diameter. Annulus is 2 to 3 µm wide. Costate circular endopores, almost double in size compared with ectopores (16 to 20 µm). Exine separates toward the apertures vestibula, about 1 µm high. A string-like structure can also be noticed emerging from the apertures (viscin thread).

Remarks. Dispersal unit. Large tetrad and pollen grain. Projected annulate ectopores. Vestibulate. Individual grains are psilate to slightly scabrate. Triporate. Presence of a string-like structure emerging from the apertures (viscin thread).

Species.Ludwigia octovalvis (Jacq.) P.H.Raven (Plate 18, figures 1–5)

Description. Coaperturate tetrahedral tetrad of large size (90–100 µm). Pollen grains with radially symmetrical, isopolar, subtriangular amb, elliptical acuminate outline in equatorial view, oblate shape. Large pollen grain (70–75 µm). Eutectate exine 3 µm thick. Visible nexine (1 µm). Tectum 0.5 to 0.7 µm thick. Indistinct columellae. Sexine increases in thickness toward the apertures (about 5 µm). Rugulate. Irregular rugulae 4 to 4.5 µm wide, irregularly distributed across the surface, increasing in width toward the apertures. Triporate. Annulate circular projected ectopores 7 to 10 µm in diameter. Well-defined annulus about 5 to 7 µm wide. Costate circular endopores, almost double in size relative to ectopores (18 to 20 µm). Exine separates toward the apertures forming vestibula 1.5 µm wide. Presence of a viscin thread coming out of the apertures.

Remarks. Coaperturate tetrad. Large tetrad and pollen grain. Rugulate. Projected annulate ecotopores. In contrast to Epilobium, the annulus is wider. Presence of a viscin thread.

Species.Oenothera arequipensis Munz & I.M.Johnst. (Plate 18, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical acuminate outline in equatorial view, oblate shape. Large size (78–90 µm). Tectate perforate exine 3.5 µm thick. Visible nexine (1 µm). Tectum 0.8 to 1 µm thick. Indistinct columellae. Psilate, punctate to slightly scabrate. Circular puncta less than 0.5 µm in diameter, distributed across the surface, but becoming conspicuously denser toward the apertures. Scabrae are usually present at the mesocolpium zone, with no pattern. Triporate. Annulate lalongate and very projected ectopores, about 18 to 22 µm in diameter. Projected ectopores give the appearance of a crater. Annulus about 3 to 4 µm wide. Costate lalongate endopores, slightly wider than the ectopores (25 to 27 µm). Exine separates toward the apertures forming vestibula (about 0.8 to 1 µm). Difficult to observe in equatorial view.

Remarks. Large size. Psilate, punctate to slightly scabrate. Triporate. Annulate lalongate and very projected ectopores. Differing from Epilobium and Ludwigia in dispersal unit.

OROBANCHACEAE Vent.

Species.Castilleja arvensis Schltdl. & Cham. (Plate 18, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, circular amb, elliptical truncate outline in equatorial view, prolate shape. Small size (22–25 µm). Tectate peforate exine 1 to 1.2 µm thick. Slightly visible thin nexine. Tectum 0.5 µm thick. Inconspicuous columellae. Exine decrease in thickness toward the apertures. Microreticulate. Circular lumina less than 0.5 µm in diameter, dispersed heterogeneously across the surface. Tricolpate to syncolpate at only one pole. Slightly marginate irregular colpi 20 to 22 µm long and 2 to 4 µm wide. The syncolpate pole resembles a fissure-like pattern. Reduced apocolpium zone.

Remarks. Small size. Inconspicuous columellae yet microreticulate pattern. Syncolporate at only one pole. Small apocolpium zone.

PAPAVERACEAE Juss.

Species.Argemone subfusiformis Ownbey (Plate 18, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, heteropolar, circular amb, circular outline in equatorial view, shape spheroidal. Medium size (50–56 µm). Semitectate exine 2 to 2.2 µm thick. Visible nexine, almost disappearing at the apertures zone. Tectum 0.5 µm thick. Conspicuous columellae 1 to 1.2 µm high. Sexine decreases in thickness toward the apertures. Fossureticulate. Heterobrochate. Irregular lumina 0.5 to 0.7 µm wide and 1 to 2 µm long, heterogeneously dispersed across the surface, but decreasing in size toward the center of the apocolpium zone. Fossulate at the apocolpium zone. Tricolpate. Marginate colpi with acute ends, about 48 to 54 µm long and 7 to 15 µm wide. Colpi with irregular borders. Margo is defined by a sexine thinning. Presence of an ornamented opercula. Very small apocolpium zone only at one pole. Difficult to observe in equatorial view.

Remarks. Medium size. Fossureticulate. Heterobrochate. Tricolpate. Reduced apocolpium zone only at one pole. Colpi with irregular borders. Presence of an ornamented opercula.

Species.Fumaria capreolata L. (Plate 18, figures 21–25)

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (45–50 µm). Eutectate exine 1.5 µm thick. Visible nexine. Tectum 0.5 to 0.7 µm thick. Inconspicuous columellae. Verrucate. Irregular shaped verrucae 1.5 to 2 µm high and 3 to 5 µm wide, slightly decreasing in size toward the apertures. Pantoporate (7–9 pores). Aspidate circular to irregular ectopores 7 to 9 µm wide. Wide open pores. Well-defined aspis 3 µm wide. Simple circular to irregular endopores 10 to 15 µm wide. Presence of an aperture membrane.

Remarks. Medium size. Verrucate. Pantoporate (7–9 pores). Wide open aspidate ectopores. Presence of an aperture membrane.

PASSIFLORACEAE Juss. ex Roussel

Species.Malesherbia scarlatiflora Gilg (Plate 18, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate shape. Large size (60–67 µm). Semitectate exine 2 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 1 µm high, decreasing toward the apertures. Reticulate. Heterobrochate. Irregular lumina 1 to 1.8 µm wide, decreasing in width toward the apocolpium zone and the apertures, but slightly increasing at the equator. Lumina with free-standing columellae. Simplicolumellate muri 0.5 µm wide. Tricolpate. Marginate ectocolpi with acute ends, about 58 to 65 µm long and 15 to 20 µm wide in polar view, but 7 to 8 µm wide in equatorial view (slightly constricted colpi). Reduced apocolpium zone.

Remarks. Large size. Reticulate pattern. Heterobrochate. Simplicolumellate. Free-standing columellae. Tricolpate.

Species.Passiflora foetida L. (Plate 18, figures 31–35)

Description. Monad, radially symmetrical, isopolar, triangular amb, prolate shape. Large size (60–75 µm). Semitectate exine, about 5 µm thick. Visible nexine. Tectum 1 µm thick. Conspicuous columellae 3 µm high. Reticulate. Heterobrochate. Irregular lumina about 4 to 8 µm wide, decreasing slightly in size at the mesocolpium. Lumina with free-standing columellae at the center. Larger lumina are located at the opercula’s surface. Simplicolumellate muri 1 to 1.5 µm thick. Second, inside the lumina there are about 3–4 free-standing columellae. Tricolpate. Simple and wide open colpi with rounded ends, about 65 to 70 µm long and 45 to 50 µm wide. Ornamented opercula 60 to 67 µm long. Orpecula is less wide than the aperture. The ornamentation is the same as the pollen grain. Opercula attached to the apertures is difficult to observe. Difficult to observe in equatorial view.

Remarks. Large size. Pollen grain string-like in shape. Large size. Reticulate. Heterobrochate. Lumina with free-standing columellae. Tricolpate. Ornamented opercula.

PHYTOLACCACEAE R.Br.

Species.Phytolacca bogotensis Kunth (Plate 18, figures 36–40)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical truncate outline in equatorial view, prolate shape. Medium size (26–30 µm). Tectate perforate exine 1 to 1.5 µm thick. Visible nexine. Tectum 0.3 to 0.5 µm thick. Slightly conspicuous columellae 0.5 µm high. Sexine slightly decreases in thickness toward the apertures. Microreticulate. Circular lumina 0.3 to 0.5 µm in diameter, homogeneously dispersed across the surface. Tricolpate. Marginate long colpi with acute ends, about 23 to 27 µm long and 5 to 7 µm wide in polar view. Colpi are constricted in equatorial view. Medium-sized apocolpium zone.

Remarks. Medium size. Microreticulate. Tricolpate. Marginate long colpi.

PIPERACEAE Giseke

Species.Peperomia galioides Kunth (Plate 19, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Very small to small size (7–10 µm). Eutectate exine 0.8 to 1 µm thick. Visible nexine. Thin tectum, less than 0.5 µm thick. Inconspicuous columellae. Verrucate. Irregular verrucae of variable shape and size, about 1 to 4 µm wide and less than 1 µm high. Inaperturate.

Remarks. Small size. Verrucate. Irregular verrucae. Inaperturate.

PLANTAGINACEAE Juss.

Species.Plantago limensis Pers. (Plate 19, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (22–30 µm). Eutectate exine 1 to 1.2 µm thick. Visible nexine. Thin tectum, less than 0.5 µm thick. Inconspicuous columellae. Verrucate. Irregular to verrucae 1 to 2 µm wide, densely dispersed across the surface. Pantoporate (5–7 pores). Simple circular to slightly irregular ectopores 3 to 5 µm in diameter. Costate circular endopores, similar in width to the ectopores. Apertures are widely separated. Sometimes the aperture has a membrane.

Remarks. Medium size. Verrucate. Pantoporate (5–7 pores). Apertures widely separated. Occasional presence of an aperture membrane.

Species.Veronica persica Poir. (Plate 19, figures 11–15)

Description. Monad, radially symmetrical, isopolar, amb circular to subtriangular, shape spheroidal to oblate. Medium size (25–33 µm). Tectate perforate exine 1.5 µm thick. Visible nexine. Tectum is 0.5 µm thick. Slightly conspicuous columellae 0.7 µm high. Sexine slightly decreases in thickness toward the apertures. Microreticulate to punctate. Heterobrochate. Circular lumina 0.5 µm in diameter or less, dispersed across the surface. Lumina decrease in width toward the apertures, turning into very small puncta. Tricolpate. Marginate ectocolpi with acute ends, about 23 to 30 µm long and 8 to 12 µm wide in polar view. Colpi are constricted in equatorial view (2 µm wide). Presence of a granulate aperture membrane, irregularly dispersed. Granulae increase in size toward the equator. Medium-sized apocolpium.

Remarks. Medium size. Ornamentation pattern is microreticulate to punctate. Tricolpate. Presence of a granulate aperture membrane.

PLUMBAGINACEAE Juss.

Species.Plumbago caerulea Kunth (Plate 19, figures 16–20)

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, spheroidal to oblate spheroidal. Large size (55–62 µm). Intectate exine 4.5 to 5 µm thick. Visible thick nexine (2 µm), thickening toward the apertures. Large conspicuous columellae 2.5 to 3 µm high, decreasing in size toward the apertures. Clavate. Large clavae (capitate columellae) 2.5 to 3 µm high. Clavae’s capita is 1 µm wide. Clavae clustered in groups of 2–5, about 3 µm wide. Clavae accommodation forms a particular negative reticulum pattern. Tricolpate. Simple colpi with acute ends, about 50 to 60 µm long and 8 to 12 µm wide in polar view. Colpi seem to be slightly conspicuous in equatorial view (4 to 5 µm wide). Small apocolpium zone.

Remarks. Large size. Nexine increasing pattern. Intectate. Clavate. Clavae clustered in groups of two to five. Tricolpate. Small apocolpium zone.

POACEAE Barnhart

Species.Aristida adscencionis L. (Plate 19, figures 21–25)

Description. Monad, bilaterally symmetrical, heteropolar, circular amb, circular outline in equatorial view, spheroidal shape. Medium size (30–35 µm). Tectate perforate exine 2 µm thick. Visible nexine. Tectum 0.5 µm thick. Slightly conspicuous columellae 0.5 µm high, decreasing in size toward the aperture. Punctate. Circular puncta 0.5 to 0.7 µm in diameter, dispersed homogeneously across the surface. Monoporate (ulcerate). Annulate circulae ectopore about 4 to 6 µm in diameter. Annulus is 2 µm wide. Costate circular endopore, slightly wider than the ectopore, about 5 to 7 µm.

Remarks. Medium size. Punctate. Monoaperturate. Annulate.

POLYGALACEAE Hoffmanns. & Link

Species.Monnina pseudopilosa Ferreyra (Plate 19, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, prolate spheroidal shape. Large size (57–63 µm). Eutectate to tectate perforate exine 1.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Inconspicuous columellae. Psilate and foveolate. Irregular foveolae 0.7 to 1 µm wide, only located at the apocolpium zone. Stephanocolporate (13 colpori). Endocingulate. Marginate ectocolpi with rounded ends, about 54 to 60 µm long and 3 to 9 µm wide. Well-defined endocingulum about 5 to 7 µm high, with a length about the circumference of the grain itself (70 to 80 µm). Medium-sized apocolpium zone.

Remarks. Large size. Psilate to foveolate. Foveolae are only located at the apocolpium zone. Stephanocolporate (13 colpori). Endocingulate.

Species.Monnina macrostachya Ruiz & Pav. (ex-Pteromonnina macrostachya (Ruiz & Pav.) B.Eriksen) (Plate 19, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical acuminate outline in equatorial view, oblate spheroidal shape. Medium size (35–40 µm). Eutectate to tectate perforate exine 1 µm. Visible nexine. Tectum less than 0.5 µm thick. Inconspicuous columellae. Psilate and foveolate. Irregular foveolae 1 µm wide, densely located in the apocolpium zone and extending to the apical part of the mesocolpium. Stephanocolporate (13 to 15 colpi). Endocingulate. Marginate ectocolpi with rounded ends, about 30 to 38 µm long and 4 to 7 µm wide. Well-defined endocingulum, about 3 to 5 µm high with a length about the circumference of the grain itself (70 to 80 µm). Medium-sized apocolpium zone.

Remarks. Medium size. Psilate to foveolate. Foveolae are only located at the apocolpium zone. Stephanocolporate (13 to 15 colpi). Endocingulate.

POLYGONACEAE Juss.

Species.Polygonum aviculare L. (Plate 19, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, circular to elliptical truncate outline in equatorial view, spheroidal to prolate shape. Medium size (30–37 µm). Tectate perforate exine 2.5 µm. Visible thick nexine (1 µm). Tectum 0.5 µm thick. Conspicuous columellae 1 µm high. Exine slightly decreases in thickness toward the apertures. Microreticulate. Circular to irregular lumina 0.3 to 0.7 µm wide. Lumina decrease in width toward the apertures. Tricolporate. Marginate ectocolpi with acute ends, about 27 to 35 µm long and 2 to 5 µm wide. Very long colpi. Lalongate endopores with acute extremes, about 2 to 3 µm high and 12 to 16 µm wide with acute ends, resembling an endocingulate condition. Endopore width forms a triangular shadow inside the grain. Reduced apocolpium zone.

Remarks. Medium size. Visible nexine. Microreticulate. Tricolporate. Wide endopores. Endopore width forms a triangular shadow inside the grain.

Species.Rumex conglomeratus Murray (Plate 20, figures 1–5)

To the best of our knowledge, this represents the first description of pollen morphology for this species. The genus, however, has been widely documented.

Description. Monad, radially symmetrical, isopolar, circular to rectangular amb, circular to elliptical outline in equatorial view, spheroidal to oblate shape. Medium size (27–30 µm). Tectate perforate exine 2 µm thick. Visible thin nexine. Tectum 0.5 µm thick. Conspicuous columellae 0.8 to 1 µm high. Microreticulate to reticulate. Homobrochate. Circular lumina of up to 0.5 µm in diameter, homogeneously dispersed across the surface, turning into a fossulate-like pattern at the mesocolpium. Tricolporate to stephanocolporate (four colpori), predominantly tricolporate. Marginate ectocolpi with acute ends, about 22 to 28 µm long and 1.5 to 2 µm wide. Costate lolongate endopores 5 to 7 µm high and 3 µm wide. Exine separates toward the apertures forming fastigia 0.5 µm high. Medium-sized apocolpium zone. When the grain is stephanocolporate, it is difficult to observe in equatorial view.

Remarks. Medium size. Exine thickening toward the apertures. Microreticulate to reticulate. Homobrochate. Tricolporate to stephanocolporate (four colpori), predominantly tricolporate. Well-defined marginate ectocolpi. Costate lolongate endopores.

PORTULACACEAE Juss.

Species.Portulaca nivea Poelln. (Plate 20, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, apolar, amb circular. Large size (87–100 µm). Eutectate exine 2 µm thick. Visible thin nexine. Tectum 0.5 µm thick. Slightly conspicuous columellae 1 µm high. Echinate. Conical echinae of variable size, about 2 to 3 µm high, slightly wider at the base (1 µm). Echinae are distributed all over the grain but locally appear clustered in small groups. Pantocolpate (12 colpi). Simple indistinct brevicolpi 15 to 20 µm long and 2 to 5 µm wide. Colpi are arranged in groups of five, forming an H-like pattern. Apertures are difficult to observe.

Remarks. Large size. Apolar. Echinate with small spines. Colpi forming an H-like pattern. Pantocolpate (12 colpi). Apertures are difficult to observe.

PRIMULACEAE Batsch ex Borkh.

Species.Lysimachia arvensis (L.) U.Manns & Anderb. (ex-Anagallis arvensis) (Plate 20, figures 11–15)

Description. Monad, radially symmetrical, isopolar, subtriangular amb, circular to elliptical outline in equatorial view, oblate spheroidal shape. Small size (20–25 µm). Tectate perforate exine 1.5 to 1.7 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 0.5 to 0.7 µm high, decreasing in size toward the apertures. Nexine generates an internal circular shadow. Microreticulate to reticulate. Heterobrochate. Circular lumina less than 1 µm in diameter. Lumina decrease in width toward the apertures. Thin but well-defined muri. Tricolporate. Slightly marginate ectocolpi with acute ends, about 20 to 22 µm long and 4 to 5 µm wide, narrowing toward the apocolpium zone. Costate lalongate endopores about 4 µm high and 7 to 10 wide. Sexine separates toward the apertures forming fastigia 1 µm high. Reduced apocolpium zone. Difficult to observe in equatorial view.

Remarks. Small size. Triangular amb. Internal circular shadow. Microreticulate to reticulate. Heterobrochate. Tricolporate. Fastigiate. Reduced apocolpium zone.

ROSACEAE Juss.

Species.Hesperomeles ferruginea (Juss. ex Pers.) Benth. (ex-Hesperomeles lanuginosa) (Plate 20, figures 16–20)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, rectangular obtuse convex outline in equatorial view, prolate spheroidal shape. Small size (20–25 µm). Eutectate exine 1 to 1.2 µm thick. Visible nexine. Tectum less than 0.5 µm thick. Inconspicuous columellae. Psilate. Tricolporate. Marginate ectocolpi with acute ends 18 to 22 µm long and 4 to 5 µm wide. Geniculate. Costate circular endopores 2 to 5 µm in diameter. Small apocolpium zone. Difficult to observe in a perfect polar view.

Remarks. Small size. Rectangular obtuse convex outline in equatorial view. Inconspicuous columellae. Psilate. Tricolporate. Geniculate. Difficult to observe in a perfect polar view.

Species.Rubus urticifolius Poir. (Plate 20, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular to circular amb, circular to elliptical truncate outline in equatorial view, spheroidal to prolate shape. Medium size (25–32 µm). Tectate perforate exine 2 to 2.2 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 0.8 to 1 µm high, decreasing in size toward the apertures but increasing toward the apocolpium zone. Striate at the equator and microreticulate at the apocolpium. Long striae 1 µm wide, dispersed across the mesocolpium zone with a fingerprint-like pattern. Irregular lumina 0.5 µm wide, densely located at the mesocolpium zone and between some striae. Tricolporate. Pontoperculate marginate ectocolpi with rounded ends, about 22 to 30 µm long and 7 to 10 µm wide in polar view. Colpi are constricted in equatorial view. Thin ornamented pontopercula. Costate circular endopores about 4 to 5 µm in diameter. Exine separates toward the apertures forming fastigia, about 0.7 µm high. Medium-sized apocolpium.

Remarks. Medium size. Spheroidal to prolate shape. Striate at the equator and microreticulate at the apocolpium. Striae with fingerprint-like pattern. Tricolporate. Pontoperculate.

RUBIACEAE Juss.

Species.Arcytophyllum thymifolium (Ruiz & Pav.) Standl. (Plate 20, figures 26–30)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, oblate spheroidal shape. Small size (20–25 µm). Semitectate exine 2.5 µm thick. Visible thick nexine (1 µm), thickening toward the apertures. Tectum 0.5 µm thick. Conspicuous columellae, about 1 µm high, decreasing in size toward the apocolpium zone. Reticulate. Heterobrochate. Pentagonal lumina 0.5 to 2 µm wide, heterogeneously dispersed across the surface. Lumina decrease in width toward the apertures. Simplicolumellate muri 0.7 to 1 µm wide. Tricolporate. Marginate ectocolpi with rounded ends, about 17 to 23 µm long and 3 to 5 µm wide, narrowing toward the apocolpium. Costate lalongate endopores 3 to 4 µm high and 7 to 8 µm wide, acute at the lateral axes. Medium-sized apocolpium. Difficult to observe in a perfect polar view.

Remarks. Small size. Reticulate. Heterobrochate. Pentagonal lumina. Tricolporate. Toward the apertures, columellae decrease in size, while the nexine increases. Colpi with rounded ends.

Ornamentation pattern. Aperture features.

Species.Randia armata (Sw.) DC. (Plate 20, figures 31–35)

Description. Decussate to tetrahedral tetrad of medium size (35–42 µm), predominantly decussate. Pollen grains with radially symmetrical, isopolar, circular to quadrangular amb, elliptical acuminate outline in equatorial view, oblate shape. Medium-sized pollen grains (25–30 µm). Eutectate exine, about 1 to 1.3 µm thick. Visible thin nexine (about 0.3 µm thick). Tectum 0.5 µm thick. Inconspicuous columellae. Psilate. Triporate. Coaperturate (Fischer’s law). Annulate circular pores 3 to 5 µm in diameter. Well-defined annulus, about 1 to 1.3 µm wide. Large apoporium zone.

Remarks. Decussate to tetrahedral tetrad. Psilate. Triporate. Coaperturate. Annulate pores. Large apoporium zone.

SAPINDACEAE Juss.

Species.Cardiospermum grandiflorum Sw. (Plate 20, figures 36–40)

Description. Monad, radially symmetrical, heteropolar, triangular amb, oblate shape. Medium to large size (40–55 µm). Semitectate exine 1 µm thick. Visible nexine. Thin tectum about 0.2 µm thick. Slightly conspicuous small columellae, about 0.5 µm high. Exine decreases in thickness toward the apertures. Reticulate. Heterobrochate. Circular to pentagonal lumina about 1 to 3 µm wide. Lumina width decreases toward the apertures and the apocolpium zone. Simplicolumellate muri 0.7 to 1 µm wide. Tricolporate and syncolporate at only one pole. Anguloaperturate. Simple straight circular ectocolpi about 25 to 30 µm long and 1 to 2 µm wide. Simple to costate projected endopores, about 7 to 10 µm in diameter. Not observed in equatorial view.

Remarks. Large size. Triangular amb. Reticulate. Heterobrochate. Syncolporate at only one pole. Anguloaperturate. Projected endopores.

Species.Sapindus saponaria L. (Plate 21, figures 1–5)

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical outline in equatorial view, oblate shape. Small size (12–20 µm). Tectate perforate exine 1 to 1.2 µm thick. Visible thin nexine. Tectum 0.5 µm thick. Inconspicuous columellae. Sexine decreases in thickness toward the apertures, while the nexine disappears. Punctate to microreticulate. Circular lumina less than 0.5 µm in diameter, dispersed across the surface. Largest lumina (0.5 µm long) located at the apocolpium zone, fossula-like in shape. Tricolporate. Anguloaperturate. Simple ectocolpi with rounded ends, about 12 to 17 µm long and 2 to 3 µm wide. Costate lalongate endopores 3 to 4 µm high and 5 to 7 µm wide. Very reduced apocolpium zone. Exine separates toward the apertures, forming fastigia (0.5 µm high).

Remarks. Small size. Triangular amb. Small size. Sexine decreases in thickness toward the apertures, while the nexine disappears. Ornamentation pattern (microreticulate). Fossula-like lumina at the apocolpium zone. Tricolporate. Anguloaperturate. Fastigiate.

SCHOEPFIACEAE Blume

Species.Quinchamalium chilense Molina (Plate 21, figures 6–10)

Description. Monad, radially symmetrical, heteropolar, circular to subtriangular amb. Small size (14–22 µm). Eutectate exine 1 µm thick. Very thin nexine. Tectum 0.5 µm thick. Inconspicuous columellae. Exine decrease in thickness toward the apertures. Microreticulate and scabrate. Irregular lumina less than 0.5 µm, dispersed equatorially across the grain and close the aperture (proximal face). The distal face of the grain lacks microreticulate ornamentation, being more scabrate. The distal face has a tetrad mark characterized by three prominent globular structures about 5 to 6 µm in diameter, enclosed by a weakening zone of the exine. Trichotomocolpate. Marginate colpi with rounded ends. Colpi ratio is about 10 to 12 µm long and 2 to 3 µm wide. Colpi arms reach the border. Margo’s surface is scabrate, about 1 µm wide.

Remarks. Small size. Heteropolar. Circular to subtriangular amb. Microreticulate (proximal face) and scabrate (distal face). Trichotomocolpate. Presence of a tetrad mark.

SCROPHULARIACEAE Juss.

Species.Alonsoa meridionalis (L.f.) Kuntze (Plate 21, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subcircular to triangular amb, elliptical truncate outline in equatorial view, prolate shape. Medium size (30–38 µm). Tectate perforate exine 1.5 µm thick. Visible thick nexine (0.7 µm). Tectum is less than 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Sexine sharply decreases in thickness toward the apertures. Microreticulate to reticulate. Irregular lumina 0.3 to 0.5 µm wide densely dispersed across the whole surface, but elongating toward the mesocolpium zone, resembling a fossulate-like pattern. Tricolpate. Simple irregular colpi with rounded ends, about 26 to 35 µm long and 8 to 15 µm wide in polar view but being constricted (about 1 µm wide) in equatorial view. Presence of a granulate aperture membrane. Medium-sized apocolpium zone.

Remarks. Medium size. Subcircular to triangular amb, Microreticulate to reticulate. Tricolpate. Simple colpi. Presence of a granulate aperture membrane. Medium-sized apocolpium zone.

SOLANACEAE Juss.

Species.Iochroma arborescens (L.) J.M.H.Shaw (ex-Acnistus arborescens) (Plate 21, figures 16–20)

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical truncate to elliptical acuminate outline in equatorial view, oblate shape. Small size (18–23 µm). Tectate perforate exine 1 to 1.2 µm thick. Visible nexine, increasing in thickness toward the aperture and forming an internal circular shadow. Tectum less than 0.5 µm thick. Inconspicuous columellae. Foveoreticulate. Irregular lumina 0.5 µm wide, dispersed homogeneously across the surface. Thin and well-defined muri (less than 0.5 µm wide). Tricolporate. Anguloaperturate. Marginate long ectocolpi with rounded ends, about 16 to 20 µm long and 2 to 3 µm wide. Costate lalongate endopores 2 to 3 µm high and 10 to 12 µm wide. Geniculate. Endopores are laterally acute. The exine separates toward the apertures forming fastigia (1 µm wide). Reduced apocolpium zone.

Remarks. Small size. Triangular amb. Small size. Nexine increases in thickness toward the apertures and forms an internal circular shadow. Tricolporate. Anguloaperturate. Long colpi. Wide endopores with acute lateral ends. Fastigiate.

Species.Cestrum auriculatum L'Hér. (Plate 21, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical outline in equatorial view, prolate shape. Medium size (26–35 µm). Eutectate exine 2 to 2.3 µm thick. Visible thick nexine (1 to 1.3 µm). Tectum 0.5 to 0.7 µm thick. Inconspicuous columellae. Exine decreases in thickness toward the apocolpium zone. Psilate. Tricolporate. Marginate ectocolpi with rounded ends, about 23 to 30 µm long and 2 to 3 µm wide. Costate lalongate endopores 5 to 7 µm high and 12 to 15 µm wide. Endopores with rounded extremes. Wide open endopores. The exine separates toward the apertures forming fastigia (0.7 to 1 µm wide). Medium-sized apocolpium zone.

Remarks. Medium size. Subtriangular amb. Inconspicuous columellae. Psilate. Tricolporate. Wide open endopores with rounded extremes. Fastigiate

Species.Datura stramonium L. (Plate 21, figures 26–30)

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical outline in equatorial view, prolate spheroidal shape. Medium size (40–48 µm). Semitectate exine 1 µm thick. Visible nexine. Tectum 0.5 µm thick. Slightly conspicuous columella less than 0.5 µm high. Fossureticulate. Heterobrochate. Irregular lumina 0.7 to 1.2 µm wide, dispersed across the surface. Lumina are elongated at the mesocolpium. Simplicolumellate muri are less than 0.5 µm wide. Muri and lumina are latitudinally aligned, giving the impression of striae. Tricolporate. Brevicolpate. Simple ectocolpi with irregular ends, about 33 to 42 µm long and 3 to 5 µm wide. Costate small lalongate endopores 2 to 3 µm high and 5 to 6 µm wide. Endopores are inconspicuous. Exine separates toward the aperture forming fastigia (1 µm wide). Large apocolpium zone. Difficult to find in equatorial view.

Remarks. Medium size. Subtriangular amb. Fossureticulate. Heterobrochate. Muri and lumina are latitudinally aligned, giving the impression of striae. Tricolporate. Brevicolpate. Small lalongate and inconspicuous endopores. Fastigiate.

Species.Exodeconus prostratus (Dombey ex L'Hér.) Raf. (Plate 21, figures 31–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical outline in equatorial view, oblate shape. Small to medium size (18–27 µm). Eutectate exine 1 to 1.5 µm thick. Visible nexine, thickening toward the apertures and forming an internal subtriangular shadow. Slightly conspicuous columellae less than 0.5 µm high. Verrucate. Circular to irregular verrucae 1 µm wide. Verrucae are homogeneously dispersed across the surface. Verrucae form a negative reticulate pattern at the apocolpium zone. Tricolporate. Marginate ectocolpi with rounded ends, about 16 to 25 µm long and 6 to 7 µm wide. Costate lalongate wide open endopores 6 to 8 µm high and 10 to 13 wide. Medium-sized apocolpium zone. Exine separates toward the apertures, forming fastigia (0.7 to 1 µm wide).

Remarks. Small to medium size. Subtriangular amb. Verrucate. Negative reticulate pattern at the apocolpium zone. Tricolporate. Fastigiate.

Species.Jaltomata umbellata (Ruiz & Pav.) Mione & M.Nee (Plate 21, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical truncate outline in equatorial view, prolate shape. Medium size (29–35 µm). Tectate perforate exine 1 to 1.2 µm thick. Visible thin nexine. Tectum 0.5 µm thick. Conspicuous columellae about 0.5 µm high. Microreticulate. Circular lumina 0.3 to 0.5 µm in diameter, homogeneously dispersed across the surface. Lumina increases in width toward the apocolpium zone and becomes smaller toward the apertures. Muri are less than 0.5 µm wide. Tricolporate. Simple ectocolpi with rounded ends, about 27 to 35 µm long and 3 to 7 µm wide. Costate lalongate endopores 3 to 5 µm high and 8 to 15 µm wide. Endopores are difficult to observe in equatorial view. Exine separates toward the apertures, forming fastigia (1.2 µm wide). Reduced apocolpium zone.

Remarks. Medium size. Subtriangular amb. Microreticulate. Tricolporate. Reduced apocolpium zone. Irregular simple colpi with rounded ends. Fastigiate.

Species.Leptoglossis lomana (Diels) Hunz. (Plate 22, figures 1–5)

–Endemic species for the Peruvian Lomas

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical truncate outline in equatorial view, prolate shape. Medium size (25–30 µm). Semitectate exine 2.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Conspicuous columellae 1.5 µm high, decreasing toward the apertures. Sexine thicker than nexine. Reticulate. Heterobrochate. Irregular lumina 1 to 3 µm wide. Larger lumina (2 to 3 µm) located at the mesocolpium zone, decreasing in size toward the apocolpium zone. Simplicolumellate muri 1 µm wide. Tricolporate. Marginate ectocolpi with acute ends, about 20 to 28 µm long and 2 to 3 µm wide. Colpi are constricted. Small simple lalongate endopores 2 to 3 µm high and 4 to 5 µm wide. Endopores are difficult to observe. Reduced apocolpium zone.

Remarks. Medium size. Subtriangular amb. Reticulate. Heterobrochate. Long columellae. Tricolporate. Constricted ectocolpi. Inconspicuous endopores.

Species.Lycium americanum Jacq. (Plate 22, figures 6–10)

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical acuminate in equatorial view, prolate shape. Small size (16–22 µm). Eutectate exine 1 µm thick. Slightly visible nexine. Tectum 0.5 µm thick. Inconspicuous columellae. Striate. Striae are as long as the grain (15 to 20 µm) and 0.5 µm wide. Inconspicuous striae. Tricolporate. Marginate ectocolpi with rounded ends, about 15 to 20 µm long and 3 µm wide. Costate circular endopores 3 to 5 µm in diameter. Conspicuous costae. Reduced apocolpium zone.

Remarks. Small size. Striate. Inconspicuous striae. Tricolporate. Conspicuous costae.

Species.Nicotiana glauca Graham (Plate 22, figures 11–15)

Description. Monad, radially symmetrical, isopolar, circular to subtriangular amb, elliptical truncate outline in equatorial view, prolate shape. Small size (20–25 µm). Tectate perforate exine 1 µm thick. Slightly visible nexine, not reaching the apertures. Tectum less than 0.5 µm thick. Slightly conspicuous columellae 0.5 µm high, decreasing toward the apertures. Microreticulate. Striate. Small circular lumina 0.5 µm in diameter, located exclusively at the apocolpium zone. Thin striae 1 to 3 µm long and 0.5 µm wide, overlapping. Striae are located at the mesocolpium zone, running from pole to pole. Tricolporate. Marginate ectocolpi with rounded ends, about 18 to 25 µm long and 8 to 10 µm wide in polar view. Colpi are constricted in equatorial view (3 µm wide). Costate circular endopores 6 to 8 µm in diameter. Slightly projected endopores. Presence of prominent aperture membranes. Reduced apocolpium zone.

Remarks. Small size. Microreticulate at the apocolpium zone, striate at the mesocolpium zone. Tricolporate. Slightly projected endopores. Prominent aperture membranes.

Species.Nolana humifusa (Gouan) I.M.Johnst. (Plate 22, figures 16–20)

–Endemic species for Peru–

Description. Monad, radially symmetrical, isopolar, circular to subtriangular amb, elliptical acuminate outline in equatorial view, oblate spheroidal shape. Medium size (26–35 µm). Eutectate exine 1.5 to 2 µm thick. Visible nexine. Tectum 0.3 to 0.7 µm thick. Conspicuous columellae 0.5 to 0.7 µm high. Striate to striato-reticulate. Thin striae 0.5 µm wide and 3 to 8 µm long. Larger striae are located at the mesocolpium zone. Striae decrease in length toward the apocolpium zone, forming a striato-reticulate pattern, with irregular lumina less than 0.5 µm wide. Striae running from pole to pole. Tricolporate. Marginate ectocolpi with rounded ends, about 23 to 34 µm long and 2 to 5 µm wide. Colpi are slightly constricted. Margo surface is psilate. Costate lalongate endopores 5 to 6 µm high and 8 to 12 µm wide. Well-defined costae. Endopores are difficult to observe in equatorial view. Reduced apocolpium zone.

Remarks. Medium size. Striate to striato-reticulate. Striate at the mesocolpium zone to striato-reticulate at the apocolpium zone. Tricolporate. Psilate margo. Well-defined endocostae. Endopores are difficult to observe in equatorial view.

Species.Salpichroa ramosissima Miers (Plate 22, figures 21–25)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, spheroidal shape. Medium size (28–30 µm). Tectate-perforate exine 1.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Slightly conspicuous columellae 0.5 to 0.7 µm high. Sexine decreases toward the apertures. Microreticulate. Circular lumina 0.3 to 0.5 µm in diameter, homogeneously dispersed across the surface. Tricolporate. Marginate ectocolpi with rounded ends, about 25 to 28 µm long and 3 to 4 µm wide. Costate lalongate endopores with acute lateral axes, about 3 to 4 µm high and 6 to 8 µm wide. Well-defined costae. Medium-sized apocolpium zone.

Remarks. Medium size. Microreticulate. Tricolporate. Wide costate endopores. Medium-sized apocolpium zone.

Species.Solanum peruvianum L. (Plate 22, figures 26–30)

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical truncate outline in equatorial view, prolate shape. Small size (15–20 µm). Eutectate exine 1.5 µm thick. Visible nexine, forming an internal circular shadow. Tectum 0.5 to 0.7 µm thick. Inconspicuous columellae. Psilate. Tricolporate. Anguloaperturate. Marginate ectocolpi with rounded ends, about 14 to 18 µm long and 2 to 3 µm wide. Costate lalongate endopores with rounded lateral axes, about 2 to 3 µm high and 4 to 8 µm wide. Well-defined costae. Exine separates toward the apertures forming fastigia (0.5 to 0.7 µm wide). Reduced apocolpium zone.

Remarks. Small size. Triangular amb. Psilate. Tricolporate. Anguloaperturate. Fastigiate.

TROPAEOLACEAE Juss ex DC.

Species.Tropaeolum majus L. (Plate 22, figures 31–35)

Description. Monad, radially symmetrical, isopolar, triangular amb, elliptical acuminate outline in equatorial view, oblate shape. Small to medium size (18–28 µm). Semitectate exine 1 to 1.5 µm in thickness. Visible thick nexine (0.5 µm). Tectum 0.2 to 0.5 µm thick. Slightly conspicuous columellae 0.3 to 0.5 µm high. Sexine decreases in thickness toward the apertures. Reticulate. Heterobrochate. Irregular lumina 0.5 to 3 µm wide. Larger lumina (1 to 3 µm) are located at the mesocolpium zone, decreasing in width toward the apocolpium zone. Simplicolumellate muri 0.5 µm wide. Tricolporate (short colpi to brevicolpate). Anguloaperturate. Marginate ectocolpi with acute ends, about 13 to 15 µm long and 3 to 6 µm wide. Costate circular endopores 3 to 5 µm in diameter. Large apocolpium zone.

Remarks. Small to medium size. Triangular amb. Reticulate. Heterobrochate. Tricolporate. Short colpi to brevicolpate. Large apocolpium zone.

URTICACEAE Juss.

Species.Pilea microphylla (L.) Liebm. (Plate 22, figures 36–40)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, circular amb, elliptical outline in equatorial view, peroblate shape. Small size (11–15 µm). Eutectate exine 1 µm thick. Nexine not visible. Tectum 0.3 to 0.5 µm thick. Slightly conspicuous small columellae less than 0.5 µm high. Exine slightly decreases in thickness toward the apertures. Microechinate. Conical microechinae less than 0.5 µm high, wider at the base (0.5 to 0.7 µm), scarcely dispersed across the surface. Space between microechinae is psilate. Diporate. Annulate circular ectopores 2 to 3 µm in diameter. Costate circular endopores 3 to 4 µm in diameter. Exine separates toward the apertures, forming vestibula (0.5 µm wide). Difficult to observe in polar view.

Remarks. Small size. Microechinate. Diporate. Annulate ectopores. Costate endopores. Vestibulate.

Species.Urtica urens L. (Plate 23, figures 1–5)

Description. Monad, radially symmetrical, isopolar, circular amb, circular outline in equatorial view, oblate spheroidal shape. Small size (14–17 µm). Eutectate exine 1 µm thick. Very thin nexine. Tectum 0.5 µm thick. Inconspicuous columellae. Psilate. Triporate. Simple circular ectopores 2 to 3 µm in diameter. Costate circular endopores, slightly smaller than the ectopores, about 1 to 1.5 µm in diameter. Large apoporium zone.

Remarks. Small size. Inconspicuous columellae Psilate. Simple ectopores. Costate endopores. Large apoporium zone.

VERBENACEAE J.St.-Hil.

Species.Lantana scabiosiflora Kunth (Plate 23, figures 6–10)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical outline in equatorial view, prolate shape. Medium size (25–35 µm). Eutectate exine 1 to 1.5 µm thick. Slightly visible nexine. Tectum 0.5 to 0.7 µm thick. Inconspicuous columellae. Psilate. Tricolporate. Slightly marginate ectocolpi with rounded ends, about 22 to 30 µm long and 4 to 5 µm wide. Costate lalongate endopores 6 to 8 µm high and 11 to 13 µm wide. Very wide endopores. Exine separates toward the apertures forming small fastigia (0.5 µm wide). Large apocolpium zone.

Remarks. Small to medium size. Subtriangular amb. Inconspicuous columellae. Psilate. Tricolporate. Very wide endopores. Fastigiate.

Species.Phyla nodiflora (L.) Greene (Plate 23, figures 11–15)

Description. Monad, radially symmetrical, isopolar, subtriangular amb, elliptical outline in equatorial view, prolate shape. Small to medium size (22–30 µm). Eutectate exine 1.2 to 1.5 µm thick. Visible nexine. Tectum 0.5 µm thick. Inconspicuous to slightly conspicuous columella 0.5 µm high. Psilate and punctate at the apocolpium zone. Tricolporate. Brevicolpate. Simple ectocolpi with rounded ends, about 20 to 27 µm of long and 2 to 5 µm wide. Endocingulate. Costate endocingulum 3 to 5 µm high and about 25 to 30 µm in circumference. Exine separates toward the apertures, forming small fastigia (0.5 µm wide). Large apocolpium zone. Difficult to observe in polar view.

Remarks. Small to medium size. Subtriangular amb. Psilate and punctate at the apocolpium zone. Tricolporate. Costate endocingulum. Fastigiate.

ZYGOPHYLLACEAE R.Br.

Species.Kallstroemia pubescens (G.Don) Dandy (Plate 23, figures 16–20)

Description. Monad, radially symmetrical, apolar, circular amb. Large size (51–60 µm). Semitectate exine 7 to 8 µm thick. Visible thick nexine (3 to 4 µm). Tectum 1.5 µm thick. Conspicuous capitate columellae 2.5 µm high. Rectangular capita. Reticulate. Homobrochate. Irregular lumina 8 to 10 µm wide, homogeneously dispersed across the surface. Simplicolumellate muri 1.5 µm wide. Pantoporate (about 45 to 50 pores). Metareticulate. Simple circular ectopores 3 µm in diameter. Costate circular endopores, wider than ectopores, about 4 to 5 µm in diameter.

Remarks. Large size. Thick nexine. Rectangular capita. Reticulate. Homobrochate. Metareticulate. Pantoporate (about 45 to 50 pores). Costate endopores, wider than ectopores.

Species.Tribulus terrestris L. (Plate 23, figures 21–25)

Description. Monad, radially symmetrical, apolar, circular amb. Medium size (35–45 µm). Semitectate exine 5 to 5.5 µm thick. Visible thick nexine (2 µm). Tectum 1 µm thick. Conspicuous capitate columellae 2 to 2.5 µm high. Circular capita. Reticulate. Homobrochate. Irregular lumina 5 to 6 µm wide, homogeneously dispersed across the surface. Simplicolumellate muri 1 µm wide. Pantoporate (about 80 to 90 pores). Metareticulate. Simple circular ectopores 1.5 to 2 µm in diameter. Costate circular endopores, slightly wider than ectopores, about 3 µm in diameter.

Remarks. Medium size. Circular capita. Reticulate. Homobrochate. Metareticulate. Pantoporate (about 80 to 90 pores). Costate endopores, slightly wider than ectopores.

PTERIDOPHYTES

ASPLENIACEAE Newman

Species.Asplenium monanthes L. (Plate 23, figures 26–30)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (30–45 µm). Wing-like cavate perispore 0.5 to 0.8 µm thick. Cavea 4 to 5 µm high. Perispore with scarce microechinae with acute tips. Granulate perispore surface with irregular granulae 1 µm wide. Single-layered exospore 1.2 to 2 µm, decreasing in thickness toward the laesura. Laevigate in distal and proximal face. Monolete. Labrate laesura 14 to 22 µm long and 1 to 2 µm wide. Laesura is 1/3 to 2/3 of the spore length. Well-defined labrum (2 µm wide).

Remarks. Medium-sized to large spore. Wing-like cavate perispore. Perispore microechinate and granulate. Monolete. Laevigate exospore in distal and proximal face. Well-defined labrum.

BLECHNACEAE Newman

Species.Blechnum occidentale L. (Plate 23, figures 31–35)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (30–37 µm). Cavate perispore 1 µm thick. Cavea 4 to 5 µm high. Scabrate perispore. Single-layered exospore 3 to 3.5 µm thick, slightly decreasing in thickness toward the laesura. Laevigate in distal and proximal view. Monolete. Labrate laesura 12 to 15 µm long and 1 to 2 µm wide. Laesura is 1/3 of the spore length. Well-defined labrum (2 to 3 µm wide). Slightly projected labrum. Retusoid.

Remarks. Medium-sized spore. Cavate perispore with scabrate ornamentation. Thick exospore. Monolete. Exospore decreases in thickness toward the laesura. Laevigate exospore in distal and proximal view.

CYSTOPTERIDACEAE Schmakov

Species.Cystopteris fragilis (L.) Bernh. (Plate 23, figures 36–40)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (25–35 µm). Echinate thin perispore 0.5 µm thick. Straight homogeneous echinae 1 to 1.5 µm long dispersed across the surface. Acavate. Single-layered exospore 1 µm thick, slightly decreasing in thickness toward the laesura. Laevigate in distal and proximal view. Monolete. Labrate laesura 17 to 22 µm long and 1 to 2 µm wide. Laesura is 2/3 of the spore length. Well-defined labrum (2 µm wide). Slightly projected labrum. Curvaturae imperfectae. Retusoid.

Remarks. Medium-sized spore. Echinate thin perispore. Monolete. Acavate. Exospore decreases in thickness toward the laesura. Laevigate exospore in distal and proximal view. Curvaturae imperfectae. Retusoid.

DENNSTAEDTIACEAE Pic.Serm.

Species.Pteridium arachnoideum (Kaulf.) Maxon (ex-Pteridium aquilinum) (Plate 24, figures 1–5)

Description. Spore free, radially symmetrical, heteropolar, triangular amb, subtriangular shape. Medium-sized spore (25–32 µm). Granulate, acavate, thin perispore 0.5 to 1 µm thick. Irregular granulae about 0.3 to 0.5 µm wide, dispersed across the surface but being predominantly dense at the distal face. Single-layered exospore 1 to 1.3 µm thick. Laevigate in distal face and proximal face. Trilete. Labrate laesura 20 to 22 µm long and 1 µm wide per arm. Laesura is 3/3 the length of the spore. Labrum of variable width, about 0.7 to 2 µm. Concave at the proximal face. Slightly retusoid.

Remarks. Medium-sized spore. Granulate perispore. Trilete. Laevigate exospore at the distal face and proximal face. Laesura is the same length as the spore. Variable width of the labrum. Slightly retusoid.

DRYOPTERIDACEAE Herter

Species.Dryopteris saffordii C.Chr. (Plate 24, figures 6–10)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal to subcircular amb, reniform shape. Medium-sized spore (30–40 µm). Cavate laevigate perispore 1.5 to 2 µm thick. High cavea with rounded tips, about 12 to 17 µm high. Perispore resembles a ‘candy envelope’. Single-layered exospore 1.5 µm thick. Homogeneously thick. Laevigate. Monolete. Simple laesura 30 to 37 µm long and 1 µm wide. Laesura is the same length as the spore. Absent labrum.

Remarks. Medium-sized spore. Laevigate and cavate perispore. Monolete. Laevigate exospore at distal and proximal face. Long laesura. Absent labrum.

Species.Elaphoglossum minutum (Pohl ex Fée) T.Moore (Plate 24, figures 11–15)

To the best of our knowledge, this represents the first morphological description of spore morphology for this species.

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal to sub-circular amb, reniform shape. Small to medium-sized spore (22–28 µm). Cavate granulate perispore 1.5 to 1.7 µm thick. High cavea 5 to 10 µm high, with well-defined ridges. Irregular granulae less than 1 µm dispersed across the perispore surface. Perispore contour has a fin-like appearance. Rarely observed without perispore. Single-layered exospore 1.5 µm thick, thinning slightly toward the laesura. Laevigate in distal and proximal face. Monolete. Labrate laesura 7 to 10 µm long and 3 µm wide. Thin labrum 0.5 µm wide. Laesure is 1/3 of the spore length.

Remarks. Small to medium-sized spore. Granulate perispore having a fin-like appearance. Monolete. Laevigate exospore in distal and proximal face. Short laesura. Labrate. Perispore is always present.

EQUISETACEAE Rich. ex DC.

Species.Equisetum bogotense Kunth (Plate 24, figures 16–20)

Description. Spore free, radially symmetrical, apolar to heteropolar, circular amb. Large spore (50–65 µm). Cavate laevigate perispore 0.5 µm thick. Cavea 5 to 8 µm high, decreasing toward the basal point of the spore. Single-layered exospore 1.2 to 1.5 µm thick. Laevigate to scabrate. Attached to the spore, there are four elaters that could be found surrounding the spore body or free (like tentacles) widening at the ends. Alete.

Remark. Large spore. Laevigate to scabrate perispore. Elaters. Alete.

OPHIOGLOSSACEAE Martinov

Species.Ophioglossum crotalophoroides Walter (Plate 24, figures 21–25)

Description. Spore free, radially symmetrical, heteropolar, circular to subtriangular amb, obtuse convex shape. Medium size (43–50 µm). Single-layered exospore 2 to 3 µm. Foveoreticulate in distal and proximal face. Heterobrochate. Irregular lumina about 3 µm in the center of the distal face, increasing in size (5 to 6 µm) toward the equator. Lumina drastically decrease in width toward the proximal face, turning into small foveolae. Muri 0.5 to 0.7 µm wide. Trilete. Labrate laesura 15 to 20 µm long and 1 to 1.5 µm wide per arm. Laesura is 2/3 to 3/3 of the spore length. Well-defined labrum 1 µm wide. Some spores had a thickening at the interradial area of the laesura, forming a torus with scabrate ornamention. Torus is 5 µm wide. Slightly retusoid.

Remarks. Medium-sized to large spore. Fovereticulate in distal and proximal face. Trilete. Labrate. Occasionally presence of a torus. Slightly retusoid.

POLYPODIACEAE J.Presl & C.Presl

Species.Pleopeltis macrocarpa (Willd.) Kaulf. (Plate 24, figures 26–30)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (48–55 µm). Single-layered exospore 3.5 to 4 µm thick. Verrucate in distal and proximal face. Irregular verrucae 1 to 1.5 µm high and 2 to 4 µm wide. Larger verrucae are predominantly located at the distal face, decreasing in size toward the proximal face. Monolete. Labrate laesura 45 to 52 µm long and 1 to 2 µm wide. Laesura is the same length as the spore. Labrum 1.5 to 3 µm wide, decreasing toward the edges of the laesura.

Remarks. Medium-sized to large spore. Monolete. Verrucate in distal and proximal face. Labrate.

Species.Serpocaulon lasiopus (Klotzsch) A.R.Sm. (ex-Polypodium lasiopus) (Plate 24, figures 30–35)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Large size (63–75 µm). Single-layered exospore 3 to 3.2 µm thick, thinning toward the proximal face. Verrucate in distal and proximal face. Irregular verrucae 2 µm high and 4 to 7 µm wide, heterogeneously dispersed across the surface. Verrucae decrease in width (2 to 3 µm) toward the proximal face, near the laesura. Monolete. Labrate laesura 30 to 35 µm long and 10 µm wide. Laesura is 2/3 the length of the spore. Labrum is verrucate, about 3 to 5 µm wide. Slightly retusoid.

Remarks. Large spore. Monolete. Verrucate in distal and proximal face. Larger and wider verrucae than in Pleopeltis. Labrate. Slightly retusoid.

PTERIDACEAE E.D.M.Kirchn.

Species.Adiantum digitatum Hook. (Plate 24, figures 36–40)

Description. Spore free, radially symmetrical, heteropolar, triangular amb. Medium size (30–40 µm). Acavate gemmate perispore 0.7 to 1 µm thick. Gemmae 2 to 3 µm high and 2 µm wide, rounded at the tip. Gemmae have a circular hollow space at the center. Single-layered exospore 1.5 µm thick. Laevigate in distal and proximal face. Trilete. Labrate laesura 13 to 20 µm long and 1 µm wide per arm. Laesura is 2/3 to 3/3 of the spore length. Labrum is 1.5 to 3 µm wide, thinning slightly toward the edge of the laesura. Not found in equatorial view.

Remarks. Medium-sized spore. Acavate and gemmate perispore. Laevigate exospore in distal and proximal face. Trilete. Labrate.

Species.Anogramma leptophylla (L.) Link (Plate 25, figures 1–5)

Description. Spore free, radially symmetrical, heteropolar, triangular amb. Medium size (42–55 µm). Single-layered exospore 3 to 3.5 µm. Fossulate. Irregularly shaped to worm-like fossulae 5 to 10 µm long and 0.5 to 1 µm wide, mainly located at the distal face but crossing to the edge of the proximal face. The space between fossulae and the surface at the proximal face is laevigate. Trilete. Labrate laesura is 20 to 25 µm long and 1.5 to 3 µm wide per arm. Laesura is the same length as the spore. Labrum 3 to 4 µm wide, with slightly verrucate ornamentation. At the interradial space, there is a torus with quadrangular verrucae (3 µm wide) in its surface, forming a negative reticulate pattern. Laesura is internally placed in the spore body, opening as valvae. Not found in equatorial view.

Remarks. Medium-sized spore. Trilete. Fossulate in the distal face, laevigate to fossulate in proximal face. Verrucate labrum. Verrucate torus with negative reticulate pattern.

Species.Hemionitis nivea (Poir.) Christenh. (ex-Argyrochosma nivea (Poir.) Windham) (Plate 25, figures 6–10)

Description. Spore free, radially symmetrical, heteropolar, triangular amb. Large size (85–90 µm). Rugulate perispore 0.5 to 0.7 µm thick. Tall, irregular rugulae 4 to 5 µm high and 2.5 to 3 µm wide. Rugulae are delimited by well-defined ridges. Rugulae are heterogeneously accommodated, giving a reticula-like appearance. Non-resistant perispore (not observed in its enterity). Single-layered exospore 1 µm thick, slightly decreasing in thickness toward the axes. Laevigate. Trilete. Labrate laesura with two different arm lengths. The larger one is 48 to 50 µm long and 7 to 10 µm wide, while the smaller ones are 37 to 40 µm long and 7 to 9 µm wide. Laesura is the same length as the spore. Labrum 1.5 to 2 µm thick. Not found in equatorial view.

Remarks. Large spore. Rugulate perispore. Laevigate exospore in distal and proximal face. Trilete. Asymmetrical laesura ratio. Laevigate labrum.

Species.Hemionitis sinuata (Lag.) Christenh. (ex-Astrolepis sinuata (Lag. ex Sw.) D.M.Benham & Windham) (Plate 25, figures 11–15)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Spore free, radially symmetrical, heteropolar, triangular amb, obtuse convex outline in equatorial view, subtriangular shape. Medium size (42–50 µm). Rugulate perispore 0.3 to 0.5 µm thick. Irregular rugulae 3 to 4 µm high and 5 to 6 µm wide. Non-resistant perispore (not observed in its enterity). Single-layered exospore 1.2 to 1.5 µm thick. Laevigate. Trilete. Labrate laesura with two slightly different arm lengths. The larger one is 22 to 27 µm long and 4 µm wide, while the smaller ones are 16 to 18 µm long and 2 to 3 µm wide. Laesura is 2/3 the length of the spore. Laevigate labrum 1 to 1.2 µm wide. Difficult to find in equatorial view.

Remarks. Medium-sized spore. Rugulate perispore less developed than in Argyrochosma. Laevigate exospore in distal and proximal face. Trilete. Slightly asymmetrical laesura ratio. Laevigate labrum.

Species.Hemionitis peruviana (Desv.) Christenh. (ex-Cheilanthes peruviana T.Moore) (Plate 25, figures 16–20)

–Endemic species for Peru–

Description. Spore free, radially symmetrical, heteropolar, triangular amb, obtuse concave outline in equatorial view, reniform shape. Medium size (40–50 µm). 2-layered exospore 3.5 to 4 µm thick, slightly decreasing in thickness toward the axes. Gemmate to verrucate. Globular verruca 5 to 8 µm wide and 3 µm high, densely spread across the surface, almost blocking the laesura. Trilete. Labrate laesura 22 to 25 µm long and 2 to 3 µm wide per arm. Laesura is the same length as the spore, reaching the axes of the spore body. Gemmate labrum 3.5 to 5 µm. Difficult to observe in equatorial view.

Remarks. Medium-sized spore. Perispore absent. Trilete. Densely gemmate-verrucate in proximal and distal face. Globular verruca. Labrate.

Species.Hemionitis ternifolia (Cav.) Christenh. (ex-Pellaea ternifolia (Cav.) Link) (Plate 25, figures 21–25)

Description. Spore free, radially symmetrical, heteropolar, triangular amb, obtuse concave outline in equatorial view, subtriangular shape. Medium to large size (40–52 µm). Rugulate perispore 0.7 to 1 µm thick. Slightly homogeneous rugula about 3 to 6 µm high and 3 to 5 µm wide. Some rugulae form a cavate-like space. Single-layered exospore 1.7 to 2 µm thick. Laevigate. Trilete. Labrate laesura with two slightly different arm lengths. The larger one is 25 to 30 µm long and 3 to 4 µm wide, while the smaller ones are 13 to 16 µm long and 2 to 3 µm wide. Laesura is the same length as the spore, reaching the axes. Laevigate labrum 1 to 1.5 µm thick.

Remarks. Medium-sized to large spore. Rugulate perispore forming cavate-like spaces. Perispore less developed than in Argyrochosma and Astrolepis. Trilete. Laevigate exospore in distal and proximal face. Slightly asymmetrical laesura. Laevigate labrum.

SALVINIACEAE Martinov

Species.Azolla filiculoides Lam. (Plate 25, figures 26–30)

Description. Asymmetrical massulae of very large size (150–170 µm; note that Plate 25, figure 16 is at 20×). Massulae surface is laevigate. Masullae have tubular tentacle-like outgrowths (glochidia) with anchor-like ends. Very resistant massulae. After five rounds of KOH, the massulae remained intact. Single microspores of radially symmetrical, heteropolar, circular amb, elliptical shape. Small microspore (12–23 µm). Single-layered exospore is about 1 to 1.2 µm thick, thinning toward the proximal face (see arrow in Plate 25, figure 30). Laevigate in distal and proximal face. Trilete. Labrate laesura 5 to 8 µm and 1 µm wide per arm. Laesura is 2/3 to 3/3 the length of the spore, reaching the axes. Laevigate labrum 0.5 µm thick.

Remarks. Microspores enclosed in massulae. Small microspore. Laevigate exospore in distal and proximal face. Trilete. Laevigate labrum.

THELYPTERIDACEAE Pic.Serm.

Species.Thelypteris glandulosolanosa (C.Chr.) R.M.Tryon (Plate 25, figures 30–35)

To the best of our knowledge, this represents the first description of pollen morphology for this species.

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (28–35 µm). Cavate and cristate perispore 0.5 to 0.7 µm thick. Cavea 5 to 6 µm high, decreasing in size toward the proximal face. Cristae 3 to 5 µm high and 6 to 7 µm wide, with small echinae 1 µm high at the borders. Space between cristae is laevigate. Single-layered exospore 1.5 to 2 µm thick, thinning slightly toward the proximal face. Laevigate at the proximal face, and laevigate to slightly microreticulate at the distal face. Slightly inconspicuous irregular lumina of less than 0.5 µm wide with well-defined thin muri, homogeneously dispersed across the surface. Monolete. Labrate laesura 23 to 25 µm long and 4 to 5 µm wide. Laesura is the same length as the spore. Labrum 2.5 to 3 µm thick. Slightly retusoid.

Remarks. Medium-sized spore. Cavate and cristate perispore. Monolete. Laevigate at the proximal face, and laevigate to slightly microreticulate at the distal face. Well-defined laevigate labrum. Slightly retusoid.

WOODSIACEAE Herter

Species.Woodsia montevidensis Hieron. (Plate 25, figures 36–40)

Description. Spore free, bilaterally symmetrical, heteropolar, ellipsoidal amb, reniform shape. Medium size (34–40 µm). Fin-like cavate, granulate and regulate perispore 0.5 µm thick. Cavea 3 to 7 µm high. Small rugulae 1 µm long, scarcely dispersed across the surface. Granulae 0.5 µm in the lower surface. Single-layered exospore 1 to 1.3 µm thick, decreasing in thickness toward the proximal face. Laevigate at distal and proximal face. Monolete. Labrate laesura 20 to 25 µm long and 2 to 5 µm wide. Laesura is 2/3 the length of the spore. Laevigate labrum 1 µm thick.

Remarks. Medium-sized spore. Cavate, granulate and regulate perispore. Monolete. Laevigate exospore at distal and proximal face. Laevigate labrum.

Morphological diversity

Among the 200 species recovered from the Lomas formations, ferns constitute 9.5% (n = 19), gymnosperms correspond to 0.5%, being represented by a single specimen (Ephedra americana; Ephedraceae), and angiosperms dominate at 90% (n = 180). The palynological forms of 114 species from the Lomas ecosystem are described for the first time (see Supplementary material, Appendix 1), although other species within the same genus may have been described elsewhere.

The most common aperture condition observed in pollen grains (n = 183) is the tricolporate type (Figure 2), accounting for 40% of the occurrences (n = 74). It is followed by the tricolpate condition at 17% (n = 32) and the pantoporate condition at 13% (n = 23). In contrast, less common aperture types include diporate, found only in Pilea microphylla (Urticaceae); trichotomosulcate, observed in Pasithea caerulea (Asparagaceae); and trichotomocolpate, only observed in Quinchamalium chilense (Schoepfiaceae). The predominant type of exine ornamentation is the reticulate type (Figure 2), accounting for 30% of occurrences (n = 55). This pattern is especially dominant in monocotyledonous families such as Alstromeriaceae, Amaryllidaceae, and Bromeliaceae, or eudicotyledonous groups such as Amaranthaceae, Caryophyllaceae, Cactaceae, Fabaceae, Lamiaceae, Malvaceae, Passifloraceae, Solanaceae, Tropaeolaceae, and Zygophyllaceae. However, echinate (17.1%; n = 31), foveolate (9.9%; n = 18), fossulate (7.7%; n = 14), striate (3.9%; n = 7), clavate (2.8%; n = 5), lophate (2.2%; n = 4) and striato-reticulate ornamentation (1.7%; n = 3) is also present (Figure 2). The prevalence of these well-developed types of ornamentation on pollen grains highlights the importance of pollination processes driven by insects or other animal vectors (e.g. birds, bats, etc.) within the Lomas vegetation. Other ornamentation types, such as punctate (20.4%; n = 37), microreticulate (14.4%; n = 26), psilate (11.6%; n = 21), microechinate (17.1%; n = 31), scabrate (4.4%; n = 8), verrucate (2.8%; n = 5), gemmate (2.2%; n = 4), rugulate (0.6%; n = 1), and plicate (0.6%; n = 1), also suggest an important contribution of anemophilous interactions (e.g. Hu et al. 2008; Winship and Hu 2010; Lu et al. 2022).

In the case of fern spores, out of the 19 genera described, nine (47.5%) are identified as trilete, another nine (47.5%) are monolete, and only one genus, Equisetum (Equisetaceae), is described as alete. The morphological features of the spores from Elaphoglossum minutum (Dryopteridaceae), Astrolepis sinuata (Pteridaceae), and Thelypteris glandulosolanosa (Thelypteridaceae) are described for the first time for the Lomas. As for sclerine stratification, we considered the ornamentation of both the perispore and exospore layers. The former is absent in 26% of cases (n = 5). We would argue that it was either not resistant to the KOH solution or was not preserved. The cavate condition of the perispore is also present in five species (26%). Among the more frequent ornamentation types for the perispore (Figure 3), we found the rugulate (21%; n = 4), granulate (21%; n = 4), laevigate (16%; n = 3), and cristate (11%; n = 2) conditions. Less common perispore ornamentation includes the echinate (n = 1) and gemmate (n = 1) types, present in Cystopteris frigilis (Cystopteridaceae) and Adiantum digitatum (Pteridaceae), respectively. Conversely, the exospore shows less diversity in structure (Figure 3), with more than 69% of fern spores exhibiting laevigate ornamentation (n = 13), followed by the verrucate ornamentation (16%; n = 3) that is present in Cheilanthes peruviana (Pteridaceae) and in the family Polypodiaceae. Other types of exospore ornamentation are found in individual species only (Figure 3), such as fossulate (Anogramma leptophylla; Pteridaceae), foveoreticulate (Ophioglossum crotalophoroides; Ophioglossaceae) and microreticulate (Thelypteris glandulosolanosa; Thelypteridaceae).

Spore dispersal for ferns is assumed to be anemophilous; however, there are reports of fern spores dispersed by the feces of animal vectors, such as insects, birds, and mammals (Hendrix 1980; Tryon 1985, 1990; Arosa et al. 2010; Sugita et al. 2013; Hervías-Parejo et al. 2019; Brock and Collier 2020). Although perispore or exospore ornamentations can exhibit well-developed patterns, there remains a gap in understanding the relationship between these morphological characteristics and potential animal affinities for dispersal. This presents an intriguing avenue for exploration, particularly considering the forced seasonality of any plant–animal interaction within the Lomas ecosystem, as well as the limited knowledge on animal-driven pollination of this flora, which have primarily focused on angiosperm-based animal diets (e.g. Maguiña and Amanzo 2016; Cairampoma et al. 2020), leaving pteridophyte species with minor attention in this regard.

Insights on palynological traits in selected plant groups

Within the Lomas palynoflora, we found that families such as Amaranthaceae, Amaryllidaceae, Apiaceae, Bromeliaceae, Caryophyllaceae, Lamiaceae, Malvaceae, Nyctaginaceae, Polygalaceae and Zygophyllaceae are conservative in exine ornamentation and aperture types, likely being stenopalynous. In contrast, families such as Cactaceae, Convolvulaceae, Cucurbitaceae, Euphorbiaceae, Fabaceae, Papaveraceae, Passifloraceae, Sapindaceae and Solanaceae show variations in exine ornamentation, with even some within-genus variation in aperture type or condition, thus being eurypalynous.

As expected, the within-family morphological diversity of the monocotyledonous families is considerably low, with the majority of pollen grains being monosulcate monads with reticulate ornamentation (e.g. Bomarea ovata within Alstroemeriaceae, Amaryllidaceae, Asparagaceae, Bromeliaceae). However, there are a few exceptions, such as Furcraea andina (Asparagaceae), dispersed as a tetrad; Pasithea caerulea (Asparagaceae), which exhibits a trichotomosulcate aperture; and Alstroemeria paupercula (Alstroemeriaceae), characterized by striate ornamentation. In contrast, certain eudicotyledonous plants show higher within-family morphological diversities. For instance, the family Asteraceae exhibits stenopalynous and eurypalinous patterns at the subfamily or tribe level (e.g. Asteroideae, Chicorioideae, Mutisioideae; Plates 4–6). The three observed genera within the Cucurbitaceae family differ from each other in ornamentation, as well as type and number of apertures (Plate 12). The family Convolvulaceae presents variable morphological features in ornamentation, as well as aperture type and number (Plates 11–12). Similarly, the family Solanaceae exhibits a wide range of ornamentation types, such as psilate, striate, (micro)reticulate, and verrucate patterns, sometimes even combining these traits, as seen in species like Iochroma arborescens, Datura stramonium, and Nolana humifusa.

Finally, two genera, Melochia and Waltheria (Malvaceae, subfamily: Byttnerioideae; Plates 16–17), were found to exhibit pollen dimorphism, potentially related to the presence of heterostylous flowers. Heterostyly involves genetically controlled heteromorphism, comprising two or three types differing in style length (Ganders 1979; Saba and dos Santos 2015; Silveira et al. 2015). These genera feature one type of pollen for longistylous flowers (reticulate) and another for brevistylous ones (microechinate and punctate). In Melochia pyramidata both morphotypes are tricolporate (Plate 16), whereas in Waltheria ovata (Plate 17) they are stephanocolporate but differ in aperture number; the reticulate type has four colpori, while the microechinate type has five.

New and contrasting observations on spore and pollen morphology

We observed some differences compared to previous morphological descriptions obtained through light-microscopy techniques. In terms of spore morphology, the species Anogramma leptophylla (Pteridaceae) has been described as verrucate or tuberculate (Tryon and Lugardon 1991; Vaganov et al. 2017); however, our findings indicate that it can also have a fossulate pattern (1–5 in Plate 25).

In the case of pollen grains, we list below the most contrasting observations, arranged alphabetically by family. Gomphrena meyeniana (Amaranthaceae) was reported by Heusser (1971; ex-G. acaulis) as having circa 48 pores per grain. However, our findings reveal an approximate range of 20 to 25 pores (16–20 in Plate 2). Proustia cuneifolia (Asteraceae) was described as microechinate by Tellería et al. (2003). However, our observations indicate a fossulate ornamentation (1–5 in Plate 6). Tourrettia lappacea (Bignoniaceae), described as psilate-foveolate or perforate (Gentry and Tomb 1979; Gentry 1980), is also found to have a fossulate ornamentation (10–15 in Plate 7). Tournefortia schomburgkii (Boraginaceae), formerly described as psilate to finely rugose (Nowicke and Skvarla 1974), is found to be verrucate as well (16–20 in Plate 7). Cleome chilensis (Cleomaceae), described as microechinate (Heusser 1971), also can exhibit a microreticulate ornamentation (16–20 in Plate 11). In the Convolvulaceae family, Cuscuta grandiflora has been described as stephanocolpate (Welsh et al. 2010), however, it can also occur as tricolpate (26–30 in Plate 11). On the other hand, Dichondra microcalyx described by Tellería and Daners (2003) as finely microechinate, is found to vary from foveoreticulate to reticulate with a heterobrochate pattern (31–35 in Plate 11). Heusser (1971) described Frankenia chilensis (Frankeniaceae) as foveolate, while we also observed a gemmate to slightly clavate ornamentation (16–20 in Plate 14). For the family Onagraceae, the species Ludwigia octovalvis has been previously described as tricolporate (Garg et al. 2021); however, according to our observations this species is triporate. Aristida adscencionis (Poaceae), previously described as having scabrate ornamentation (Perveen 2006), is found here to have a punctate ornamentation (21–25 in Plate 19). Lysimachia arvensis (Primulaceae), described as tricolpate (Shiha 2020), is also found to be tricolporate (11–15 in Plate 20). Within the Solanaceae, Datura stramonium has been described as striate at the mesocolpium and coarsely reticulate-rugulate at the apocolpium zone (Perveen and Qaiser 2007a); however, we observed a fossureticulate ornamentation with a heterobrochate pattern (26–30 in Plate 21). In the case of Iochroma arborescens, the exine has been described as tectate and its ornamentation as reticulate (Murry and Eshbaugh 1971); however, our observations show a tectate perforate tectum with a foveoreticulate ornamentation (16–20 in Plate 21). Lycium americanum has been described as striate at the mesocolpium and rugulate at the apocolpium (Bernardello and Luján 1997); nonetheless, our specimens have an exclusively striate ornamentation (6–10 in Plate 22). Nicotiana glauca, described by Heusser (1971) as striate, includes grains with a microreticulate ornamentation at the apocolpium and a striate pattern only at the mesocolpium (11–15 in Plate 22). Within the Urticaceae family, Urtica urens has been described as microechinate (Sorsa and Huttunen 1975); however, pollen grains observed herein lack supratectal elements, having a psilate ornamentation (1–5 in Plate 23). Finally, Phyla nodiflora (Verbenaceae), described as having psilate to punctate ornamentation and a tricolporate aperture (Heusser 1971; Perveen and Qaiser 2007b), shows a punctate ornamentation at the apocolpium and a psilate pattern at the mesocolpium, with apertures exhibiting an endocingulate condition.

These observations and morphological intricacies should be investigated in greater detail using high-resolution techniques, such as confocal microscopy and scanning electron microscopy, to achieve a comprehensive understanding of the observed variations in ornamentation and aperture characteristics.

Foreword on samples yielding negative results

The actual number of species collected for palynological analysis from the MHN-UNMSM Herbarium was 251. However, after the KOH procedure, 51 species, ascribed to 17 families, did not yield any (or enough) palynomorph traces (Supplementary material, Appendix 1). Nine of these sterile samples correspond to endemic species of the Lomas ecosystem. The negative results can be attributed to either the condition of the herbarium specimen or the plants having already released their pollen prior to collection. Additionally, the flowers of some xeric species are too small to extract anthers or to determine the presence of pollen (e.g. Crassula connata and Nama dichotoma). Another factor to consider as potentially inducing negative results could be the pollen size. For instance, genera such as Galium (Rubiaceae) and Crassula (Crassulaceae) possess small pollen grains (<15 µm) according to the palynological literature (Abdel Khalik et al. 2007; Shehata et al. 2023), and thus pollen grains may have been accidentally discarded during the sample preparation. Therefore, these 51 species will undergo reprocessing with the aim of completing the palynological spectrum at the genus level for the Peruvian Lomas.

In the western Peruvian lowlands of the Andean region, the seasonal greening of the landscape promotes the development of a diverse and highly endemic flora, which locally can interrupt the extended hyperarid landscape. These vegetation patches, known as Lomas formations, provide key ecosystem services for numerous species, including humans. We present the palynological features, observed through light microscopy, of 200 genera out of the 353 currently described, including 37 endemic species. Specifically, we provide information for one gymnosperm species (0.5%), 180 angiosperms (90%), and 19 pteridophytes (9.5%). The palynological forms of 114 species from the Lomas ecosystem are described for the first time (see Supplementary material, Appendix 1), although other species within the same genus may have been described elsewhere. We discuss some key morphological observations, noting differences when comparing our material with existing descriptions. Furthermore, given the morphological diversity of the palynoflora presented here, a summary table outlining key morphological features and serving as morphology-based search index is also provided (Supplementary material, Appendix 3).

Georeferenced and voucher-related palynological reference materials from xeric vegetation, such as those presented herein, are essential for morphological comparisons, enabling the testing of diverse evolutionary, biogeographic, and ecological hypotheses. Therefore, this work serves as a reference for upcoming (paleo)palynological studies addressing the evolution of dry floras, plant–animal interactions, landscape changes, and human–plant interactions from prehistoric to historical settlements.

The authors acknowledge support from the MHN-UNMSM Herbarium for providing the samples for building the first palynological collection for the Peruvian Lomas, now housed at the Biogeosciences laboratory of the Universidad Peruana Cayetano Heredia (UPCH) and the Herbario Sur Peruano (HSP) of the Instituto Científico Michael Owen Dillon (IMOD). We express our sincere appreciation to GCO for guidance on new language tools and to S. Simon for logistical and administrative support. We thank C. Diaz-Beltran (U. Bosque, Colombia) for his help in gathering flora inventories from Lomas formations. We dedicate this research to the residents of Atiquipa for their efforts aimed at preserving the landscape, biodiversity, and cultural heritage of the area.

AXEL TEJADA is a biology undergraduate student at the Universidad Nacional Federico Villarreal (Peru). His research interests focus on botanical evolution, taxonomy, and palynology. He is interested in understanding how Peruvian ecosystems have changed and developed over time. https://orcid.org/0000-0003-1098-0367

JUAN-FELIPE MONTENEGRO is a biologist specialized in palynology and plant morphology. Currently, he is developing his master’s thesis at the Biogeosciences Laboratory at the Universidad Peruana Cayetano Heredia (Peru). His thesis focuses on reconstructing the middle Miocene vegetation of the southern Peruvian coast based on leaf fossils, wood, and pollen assemblages. https://orcid.org/0000-0001-5165-183X

MARÍA ISABEL LA TORRE is a faculty member at the Universidad Nacional Federico Villarreal (Faculty of Natural Sciences and Mathematics). She holds a master’s degree in tropical botany from the Universidad Nacional Mayor de San Marcos (Peru), and specializes in taxonomy of the Poaceae family and other vascular plants. https://orcid.org/0000-0001-6695-4083

BRENDA OROSCO is currently doing an internship at the Smithsonian Tropical Research Institute (STRI) in Panama. She is completing her undergraduate thesis, which centers around the pollen morphology of both fossil and extant Neotropical species of Sanguisorbeae (Rosaceae). Her research focuses on reconstructing tropical ecosystems through the analysis of modern and fossilized pollen samples. https://orcid.org/0009-0007-5449-1510

DIANA OCHOA is a Marie Sklodowska-Curie Postdoctoral Fellow at Salamanca University (Spain) and an invited researcher at Universidad Peruana Cayetano Heredia (Peru). Her research focuses on understanding the onset and evolution of the Humboldt Current and its role in shaping global and regional climates, ecosystems, and landscapes. She is also interested in understanding the evolution of the South American Pacific coastal floras, varying from tropical forest to mangroves to dry forests and deserts. https://orcid.org/0000-0001-6242-4202.

DO: conceptualization; ATF, JFM, BO, MLT, DO: methodology; ATF, JFM, DO: investigation; ATF, DO: visualization; DO: supervision; ATF, DO: writing – original draft; ATF, JFM, BO, MLT, DO: writing – review and editing.

No potential conflict of interest was reported by the authors.

All data are available as supplementary materials.