Abstract Although Permian fossils have been known from the Parnaíba Basin for two centuries, and some faunal and flora elements are well known worldwide, research on the fossil assemblages from this basin has lagged relative to other, more accessible basins. In the last decade, however, there has been a significant increase in the study of fossils from the two Permian units of the basin: the Pedra de Fogo and Motuca formations. The goal of this contribution is to synthesize and update the existing data on the Permian macrofossils from these formations, and to use them to address biostratigraphic, palaeoenvironmental and palaeogeographical questions. The Pedra de Fogo and Motuca formations are likely to be Cisuralian in age. Contrary to previous reports, there is more than one stratigraphic interval that preserves petrified fossil plants. The possible marine influence proposed for the Pedra de Fogo Formation must be reassessed based on the strongly terrestrial character of its fossil assemblages. Palaeoenvironmental and palaeoclimatic conditions are inferred to be wetter than is typically predicted for this region of the globe based on climatic modelling. Despite sharing some taxa with the Euramerican and Gondwanan biogeographical provinces, the Parnaíba Basin was likely to have been part of a distinct biogeographical province, as indicated by the high degree of endemism displayed by its Permian floras and faunas.

A correlation between plant zones and palynozones within a sequence-stratigraphic framework for the upper Paleozoic rocks of the Paraná Basin, Brazil, is attempted for the first time. Our study indicates that (1) the stratigraphic boundaries (lithostratigraphic boundaries and sequence boundaries) are not coincident with most of the biostratigraphic horizons; (2) the boundaries between palynozones and plant zones are also not coincident with each other; and (3) the boundaries of palynozones lie near the maximum flooding surfaces through the interval analyzed. The emerging pattern suggests that plant zones are mostly controlled by depositional processes and palynozones by climate-driven changes. Therefore, the plant zones correspond to distinct ecofacies, and are better regarded as ecozones rather than as biozones. On the other hand, the climatic changes that affected the palynofloras were related directly to the most significant transgressive events, suggesting a link with eustatic oscillations caused by Early Permian Glacial-Interglacial Phases. Aims of further work may include (a) evaluation of taphonomic controls in plant-bearing beds, (b) better understanding of the relation between the plant-bearing strata and their equivalent palynologic zones, (c) correlation between palynologic and paleobotanic data and the sequence-stratigraphic framework already established in other areas, and (d) improvement of the chronostratigraphic chart of the basin through the discovery of layers suitable for radiometric dating.

The Bashkirian to Sakmarian-Artinskian Itararé subgroup provides a record of the evolution of the Permian-Carboniferous glaciation in the Paraná Basin (Brazil). The glaciogenic succession was deposited under the influence of glaciers incoming from southwestern Africa. This paper presents an overview of the third-order sequence stratigraphy of that succession and a biostratigraphic summary, showing that: (1) the most complete and thick outcrop portion of the glaciogenic succession occurs in the northeastern part of the Paraná Basin, where several (at least nine) major cycles of ice advance and retreat can be recognized during the development of the Itararé subgroup; (2) biostratigraphically, two well-defined stratigraphic gaps within the Permian-Carboniferous succession are recognized, one within the Itararé subgroup, related to the Lapa–Vila Velha incised valley fill, and another at the Itararé–Rio Bonito boundary, both of which represent regional sequence boundaries; and (3) the transition between palynozones Crucisaccites monoletus and Vittatina costabilis is associated with the maximum flooding surface represented by the marine Lontras Shale, a regional marker bed located in the upper third of the glaciogenic succession.