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Four proetid trilobite species, Chuanqianoproetus guizhouensis Yin in Yin and Li, 1978, C. shuangheensis Wu, 1977, C. sp., and Latiproetus guizhouensis Yin in Yin and Li, 1978, are described from the Ningqiang Formation in Ningqiang County, Shaanxi, China. They are middle Telychian (Llandovery, Silurian) in age. Chuanqianoproetus and Latiproetus are both regarded as members of the subfamily Warburgellinae; the former has been considered to be a junior subjective synonym of Astroproetus, but on the basis of its morphology we argue here that they represent two independent genera. The poorly sorted bioclastic grainstones containing trilobite sclerites may indicate their deposition in turbulent conditions on an open marine platform.

A Foliomena fauna is reported for the first time from the Tarim paleoplate, and stratigraphically from the Yinpingshan Formation (upper Katian, Upper Ordovician) of Querqueke, Kuruktag region, northeastern Tarim, southern Xinjiang, Northwest China. The fauna includes seven species of brachiopods, amongst which three are new and four indeterminate: Anomaloglossa ? sp., Orbiculoidea ? sp., Foliomena xinjiangensis n. sp., Sericoidea minuta n. sp., Kassinella tarimensis n. sp., Rostricellula ? sp., and Anazyga ? sp. These species formed a Sericoidea - Kassinella Association, characterized by very small and well-preserved brachiopods, and well-developed laminations in its hosted mudstone, indicating a deep water environment (corresponding to lower BA5 to BA6). The faunal and sedimentological features suggest its affinity to the typical Foliomena faunal group of deep water origin. Numerical analyses show that the Foliomena fauna in late Katian time differentiated into two major paleogeographically related groups, and the Tarim association has a close faunal affinity to the representatives of this fauna in South China, indicating an active faunal exchange between Tarim and South China before the end-Ordovician mass extinction.