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The end-Permian mass extinction (EPME) led to a severe terrestrial ecosystem collapse. However, the ecological response of insects-the most diverse group of organisms on Earth-to the EPME remains poorly understood. Here, we analyse beetle evolutionary history based on taxonomic diversity, morphological disparity, phylogeny, and ecological shifts from the Early Permian to Middle Triassic, using a comprehensive new dataset. Permian beetles were dominated by xylophagous stem groups with high diversity and disparity, which probably played an underappreciated role in the Permian carbon cycle. Our suite of analyses shows that Permian xylophagous beetles suffered a severe extinction during the EPME largely due to the collapse of forest ecosystems, resulting in an Early Triassic gap of xylophagous beetles. New xylophagous beetles appeared widely in the early Middle Triassic, which is consistent with the restoration of forest ecosystems. Our results highlight the ecological significance of insects in deep-time terrestrial ecosystems.

A new genus and species of snakefly, Laiyangoraphidia delicata gen. et sp. nov., is described from the Lower Cretaceous Laiyang Formation, eastern Shandong, China. This is another genus characterised by the short pterostigma in Mesoraphidiidae. Its complex branching structure and the absence of crossveins between and inside RP and MA suggest it may be a transitional taxon between Grammoraphidia and Proraphidia. This discovery enriches our knowledge on the biodiversity of Raphidioptera from the Lower Cretaceous Laiyang Formation. [ABSTRACT FROM AUTHOR]

A distinct coal break occurs widely in the late Early Jurassic in Central Asia, the cause of which, however, is still debated largely due to the uncertainty of its age constraint. In the Junggar Basin of northwestern China, this coal break coincides with the Sangonghe Formation, which is well exposed along the basin margins, and is mainly composed of lacustrine deposits rich in a variety of fossils, including plants, pollens and spores, bivalves, clam shrimps, insects and some vertebrates. Here we name them as the Sangonghe biota and review their biostratigraphic framework. The Sangonghe biota constrains the Sangonghe Formation to the late Pliensbachian to the early Aalenian. Abundant thermophilous plants and Classopollis, together with frequent occurrences of red beds and carbonate nodules in the middle part of the Sangonghe Formation, are indicative of an arid climate in Central Asia at that time. This arid interlude should be responsible for the coal break, which may be related to the global warming in the early Toarcian. However, more precise dating evidence is needed to substantiate this. [ABSTRACT FROM AUTHOR]

The non-marine bivalve Ferganoconcha occurred widely in palaeolakes in the high-middle latitude of northern China, Siberia and Central Asia during the Early and Middle Jurassic and was an important member of these lacustrine ecosystems. The diagnostic features and phylogenetic position of Ferganoconcha are still under debate. Here, based on nearly one hundred of Ferganoconcha specimens from the lacustrine and fluvial facies of the Junggar Basin in northwestern China, it is clearly shown that its most important distinctive features are the thin and flatted to weakly inflated shell covered with wrinkled ornament and the ligament is well-developed. This kind of shell indicate that the Ferganoconcha is a weak suspension feeder, burrowing rapidly and living in fine-soft substrata of the 'low energy' environments. In addition, we conclude that the dispersal pattern of the Ferganoconcha generally followed the cool to temperate and humid paleoclimate zone in northern China during the Early to Middle Jurassic, making the genus a possible palaeclimatic indicator. [ABSTRACT FROM AUTHOR]