Abstract The Kasimovian Stage is the lower stage of the Upper Pennsylvanian Subsystem, in which a series of considerable biotic and abiotic events happened and changed the Earth. The Variscan orogeny and the Late Paleozoic Glaciation are two major events that caused geographical isolation of marine faunas and difficulties for a global correlation of biostratigraphy. Regional timescales of the Kasimovian across major continents are reviewed here. A global correlation of the Kasimovian is tentatively established based on a detailed review of major fossil groups such as conodonts, fusulines and some macrofossils. The index taxon for the base of the Kasimovian Stage has not been selected. The conodont species Swadelina subexcelsa , Idiognathodus heckeli , I. turbatus and I. sagittalis have good potential. Among them, I . heckeli is considered the best marker for the base of the Kasimovian Stage because it can mark a bioevent in a wide geographical range, and more importantly, it has a clear taxonomic definition within a phylogenetic lineage. The fusuline Montiparus might be regarded as an auxiliary marker to define the base of the Kasimovian based on its wider distribution. Other proxies, i.e. isotopic dating and strontium, carbon and oxygen isotopic stratigraphy throughout the Kasimovian, are also reviewed. The Global Boundary Stratotype Section and Point (GSSP) candidates for the Kasimovian Stage include the Naqing section, South China, the Usolka section, South Urals and the Afanasievo section, Moscow Basin. The Naqing section is regarded as the most appropriate GSSP candidate in terms of its complete sedimentary succession, well-recorded conodont lineages and well-studied bio-, chemo- and cyclo-stratigraphy.

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: A review of Permian fusuline biostratigraphy is made in this paper in order to improve the correlation of Permian strata globally. Permian fusuline biostratigraphy in the Tethyan and Panthalassan regions can be correlated roughly because the fusulines had good faunal communications between these two regions. However, fusuline faunas from the North American Craton region were devoid of almost all neoschwagerinids and dominated exclusively by schwagerinids during the Guadalupian (Middle Permian) because of the blockage caused by the vast Pangaea supercontinent. This renders the correlation of Middle Permian biostratigraphy and chronostratigraphy between the Tethyan region and North American region challenging. Significant evolutionary key points in fusulines include the first occurrence of Pseudoschwagerina or Sphaeroschwagerina during the earliest Permian, first occurrence of Pamirina and Misellina during the Yakhtashian and Bolorian, and the extinction of all schwagerinids and neoschwagerinids by the end of the Midian.