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The article focuses on a study which examined brachiopod assemblages from Qingyan, Guizhou Province, China. Specimens of brachiopod were collected from the Qingyan Formation of Anisian. The total number of brachiopod species identified from 21 genera was 31, while seven assemblages were recognized. Results of the study showed that the Diholkorhynchia sinensis dominated the D assemblage. It also observed a stepwise diversification for the brachiopod faunas during the recovery/radiation time.

The article focuses on a study which marine ecosystem changes in the Permian-Triassic (P-T) mass extinction and rebuilding in Early-Middle Triassic in the Qingyan area in Guizhou, Southwest China. Information on the characteristics of the Anshun Formation and the Changsingian ecosystem at Qingyan is provided. According to the study, marine ecosystems at the Mafengpo Member have degraded to the earliest Triassic level and features high-abundance, low-diversity ammonoid communities.

Abstract: The Middle Triassic Qingyan Formation at its type section, the Qingyan section of Guizhou, Southwest China, yields more than 300 species belonging to 17 fossil groups, which mark the radiation of benthic organisms following the end-Permian mass extinction. This study intends to establish a primary conodont biostratigraphical succession through the Lower and Middle Triassic sequence at Qingyan to provide a time framework for the understanding of the recovery and radiation process from the mass extinction. A total of 30 species in 8 conodont genera are stratigraphically significant and assigned to the Neospathodus dieneri, Neospathodus cristagalli, Neospathodus waageni, Neospathodus homeri, Chiosella timorensis, and Neogondolella cf. bulgarica Zones in ascending order. Most conodont zones correlate well with their counterparts recognized from elsewhere in China and even worldwide. The first appearance of Ns. waageni marks the Induan–Olenekian boundary, which is placed at the lower–middle part of the Luolou Formation, 121.47m above the Permian–Triassic boundary. The Olenekian–Anisian (Early–Middle Triassic) boundary is here defined by the first occurrence of Chiosella timorensis at the base of the Qingyan Formation. Although no conodonts retrieved from the upper Qingyan Formation containing the extraordinarily diverse biota, i.e. the Qingyan Biota, stratigraphical correlation with the neighbouring conodont-bearing sections in Guizhou and the ammonoid zones suggest that the Qingyan Biota has an age of early late Anisian (early–Middle Triassic). [Copyright &y& Elsevier]

Abstract: Ether lipids such as non-isoprenoid mono and dialkyl glycerol ethers (MAGEs and DAGEs) and archaeol have been found in carbonate rocks and mud rocks deposited during the Early and Middle Triassic (250–240Ma). The oldest previous discovery of ether lipids is from Cretaceous black shale deposited during the Albian (112Ma). Paleoenvironmental reconstruction using ether lipids has therefore not been conducted on pre-Cretaceous sediments. Archaeol derives from archaea (e.g. methanogenic, methanotrophic, halophilic and thermophilic archaea). The non-isoprenoid DAGEs and MAGEs likely derive from sulfate-reducing bacteria (SRB), which are restricted to anaerobic environments. The presence of ether lipids thus indicates that anoxic conditions expanded in the depositional and/or water column environment in the Qingyan area during the Early–Middle Triassic. These ether lipids may be useful for the reconstruction of paleoredox conditions and paleoecosystems in the area. Furthermore, their occurrence suggests that paleoenvironmental reconstruction using ether lipids may be possible throughout the Mesozoic and Cenozoic. [Copyright &y& Elsevier]