Abstract Tetrapod (amphibian and amniote) fossils of Carboniferous age are known almost exclusively from the southern part of a palaeoequatorial Euramerican province. The stratigraphic distribution of Carboniferous tetrapod fossils is used to identify five land-vertebrate faunachrons: (1) Hortonbluffian (Givetian–early Visean), the time between the first appearance datum (FAD) of tetrapods to the beginning of the Doran; (2) Doran (late Visean–early Bashkirian), the time between the FAD of the baphetid Loxomma and the beginning of the Nyranyan; (3) Nyranyan (late Bashkirian–Moscovian), the time between the FAD of the eureptile Hylonomus and the beginning of the Cobrean; (4) Cobrean (Kasimovian–late Gzhelian), the time between the FAD of the eupelycosaur Ianthasaurus and the beginning of the Coyotean; and (5) Coyotean (late Gzhelian–early Permian), the time between the FAD of the eupelycosaur Sphenacodon and the beginning of the Seymouran. This biochronology provides insight into some important evolutionary events in Carboniferous tetrapod evolution.

Abstract The Carboniferous chronostratigraphic scale consists of two subsystems, six series and seven stages. Precise numerical age control within the Carboniferous is uneven, and a global magnetic polarity timescale for the Carboniferous is far from established. Isotope stratigraphy based on Sr, C and O isotopes is at an early stage but has already identified a few Sr and C isotope events of use to global correlation. Cyclostratigraphy has created a workable astrochronology for part of Pennsylvanian time that needs better calibration. Chronostratigraphic definitions of most of the seven Carboniferous stages remain unfinished. Future research on the Carboniferous timescale should focus on Global Stratotype Section and Point (GSSP) selection for the remaining, undefined stage bases, definition and characterization of substages, and further development and integration of the Carboniferous chronostratigraphic scale with radioisotopic, magnetostratigraphic, chemostratigraphic and cyclostratigraphic tools for calibration and correlation, and the cross-correlation of non-marine and marine chronologies.

Abstract The Late Pennsylvanian was a critical juncture in tetrapod evolution when many terrestrially adapted taxa first appeared. The Middle Pennsylvanian (Moscovian) tetrapod record reflects a taphonomic megabias that favoured preservation, discovery and collection of aquatic tetrapods that lived in wetland palaeoenvironments (‘coal swamps’). The Kasimovian tetrapod record is limited to seven localities, all but one in the USA, and two of which are singleton records, so it is less abundant, diverse or widespread than earlier Moscovian and later Gzhelian tetrapod records. This ‘Kasimovian bottleneck’ hinders interpretation of tetrapod evolutionary events across the Middle–Late Pennsylvanian boundary. Significant changes did take place across that boundary, but they were spread out over Moscovian through Gzhelian time. Many of the perceived changes in tetrapods across the Middle–Late Pennsylvanian boundary are largely artefacts of facies changes and the Moscovian tetrapod taphonomic megabias and of the limited fossil record of Kasimovian tetrapods. Therefore, there is no simple link between Late Pennsylvanian tetrapod evolutionary events and changes in climate and vegetation.

Abstract In Europe, North Africa and Asia Minor, the remains of Pennsylvanian sedimentary basins bearing continental deposits either intimately mixed with shallow-marine strata or deposited in exclusively continental settings are preserved. Long-lasting research on these basins allowed the definition of regional stages and substages based on marine fauna and terrestrial flora, later extended by terrestrial and freshwater faunal biostratigraphies. Glacioeustatically driven marine bands provide laterally widespread correlation markers; however, where such bands are missing only biostratigraphic control exists. Resolution of biostratigraphic zonations combined with gaps in sedimentary successions and variable quality of the fossil record throughout the basin fills do not allow in all cases a precise correlation between the Pennsylvanian basins in Europe and, in turn, the timing of tectonic, climatic and biotic events, and thus an absolute complete understanding of the response of terrestrial and freshwater biota to climate changes across eastern tropical Pangaea. A helpful tool is new radioisotopic ages of intercalated volcaniclastics that reveal the partial diachroneity of some widely used biostratigraphies. We attempt to present the current state of the art to stimulate further research to mitigate gaps in our knowledge.