A new Early Triassic brachiopod fauna from southern Tibet, China: Implications on brachiopod recovery and the late Smithian extinction in southern Tethys

Abstract

Brachiopods suffered high levels of extinction during the Permian–Triassic crisis, and their diversity failed to return to Permian levels. In the aftermath of the Permian-Triassic mass extinction, brachiopods were extremely rare worldwide, especially in the southern hemisphere. Here, we report a new Early Triassic brachiopod fauna from the Selong section in southern Tibet, China. A new genus and three new species have been identified: Selongthyris plana Wang and Chen n. gen. n. sp., Piarorhynchella selongensis Wang and Chen n. sp., and Schwagerispira cheni Wang and Chen n. sp., which are typical. The ontogenies and internal structures of these three new species are described in detail. This brachiopod fauna corresponds to the Neospathodus pakistanensis and Neospathodus waageni conodont biozones and Kashmirites and Anasibirites ammonoid biozones, indicating a late Dienerian to late Smithian age. The post-extinction recovery of brachiopods in the Himalayas may have begun by the early Smithian of the Early Triassic. In addition, these species did not persist into the Spathian substage, suggesting that the newly evolved brachiopods in the southern Tethys were severely affected by the late Smithian extinction event.UUID: http://zoobank.org/f8fc8ced-432c-41d2-8c6c-d17bca527109

A Highly Diverse Olenekian Brachiopod Fauna from the Nanpanjiang Basin, South China, and Its Implications for the Early Triassic Biotic Recovery

“…There are only several Olenekian brachiopod fauna found worldwide so far ( Table 1 ), mainly including those reported from western North America [ 20 , 21 ], the Balkan region [ 24 ], the Far East of Russia [ 23 ], north-western China [ 22 ], and Tibet [ 25 ]. Compared with those fauna, the Datuguan brachiopod fauna shows the highest richness (14 species in nine genera in the Olenekian) ( Table 1 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 ).…”

“…In the post-extinction interval, the Induan (especially Griesbachian) brachiopod fauna was mainly characterised by holdovers (26 genera), and the newcomers, which included a few genera of Rhynchonellida (seven genera) and Spiriferinida (two genera) ( Figure 3 ). If we exclude the holdovers in the earliest Induan fauna, the Smithian and most Induan brachiopod fauna generally have very low diversity [ 18 , 19 , 25 , 67 ], which should be categorised in the ‘survival stage’ of the overall recovery process.…”

“…In the post-extinction interval, Induan brachiopod fauna is mostly reported from South China, characterised by the transient Permian holdovers (e.g., Paryphella , Fusichonetes , Prelissorhynchia , Paracrurithyris ) [ 13 , 14 , 15 ], lingulids [ 16 , 17 ] and a few newcomers (e.g., Meishanorhynchia , Lichuanorelloides ) [ 18 , 19 ]. In the Olenekian, brachiopod fauna is rarely reported (Idaho, western USA [ 20 , 21 ]; Qilian Area, north-western China [ 22 ]; Primorye, Russia [ 23 ]; Romania [ 24 ]; and Tibet, China [ 25 ]), and have very low diversity in most of these areas. Up until now, glimpses into the evolutionary dynamics of Early Triassic brachiopods (excluding Permian holdovers) show very low diversity and few occurrences.…”

Hyperthermal-driven anoxia and reduced productivity in the aftermath of the Permian-Triassic mass extinction: a case study from Western Canada

“…Only a handful of studies have produced continuous environmental records across the entire Lower Triassic interval of environmental instability at the regional or local scale (e.g., Shen et al, 2015;Lau et al, 2016;Grasby et al, 2021;Ishizaki and Shiino, 2023;Saito et al, 2023). Analysis of paleobiologic trends during this period suggests that recovery was often sluggish or reset by persistent environmental stresses (Pietsch et al, 2014;Song et al, 2014;Woods et al, 2019), resulting in a slow biotic rebound that frequently stretched well beyond the earliest Triassic, to perhaps as late as the early middle Triassic (Anisian) (e.g., Schubert, 1989;Hallam, 1991;Twitchett and Wignall, 1996;Boyer et al, 2004;Pruss and Bottjer, 2004;Twitchett and Barras, 2004;Nützel and Schulbert, 2005;Baucon and De Carvalho, 2016;Golding, 2021;Wang et al, 2022;Zhu et al, 2022). It is important, therefore, to produce longer palaeoenvironmental records that allow us to better understand the complex relationship between biotic trends and environmental conditions, and, as a result, how the planet and its biota recover from protracted, multifaceted environmental crises, including the hyperthermal event associated with the PTME or our modern climate emergency.…”