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Well-preserved internal and external moulds of a shumardiid species are described from the late Furongian (Late Cambrian) “Fengshan Formation” at Poben, Napo, southwestern Guangxi, which is close to the type locality of Shumardia orientalis, the type species of Eoshumardia. All features observed on the internal moulds indicate that the new material is definitely S. orientalis, whereas the morphology of the external moulds indicates that S. orientalis should be referred to Koldinioidia. The change of generic assignment of the type species means that Eoshumardia is a junior synonym of Koldinioidia.  相似文献   
2.
On the basis of representative collections made from seven measured sections in western Hubei and Hunan, four early Llanvirn and five late Llanvirn-early Caradoc trilobite biofacies are distinguished along a bathymetric gradient from shallow to deep outer shelf. The diversity and relative abundance of mesopelagic cyclopygids gradually increased southwards or seawards. According to the facies association exhibited in the region, the upper limit of living depth for different forms is inferred as follows: 1) more than 70 m (M. (Microparia)); 2) less than 100 m (M. (Quadratapyge), Pricyclopyge, Aspidaeglina); 3) at approximately 100 m (Cyclopyge); and 4) more than 100 m (Symphysops, Psilacella). Benthic forms were absent in the deep outer-shelf basin because of stagnant conditions. In shallower sites of the outer shelf, genera of nileids in the carbonate facies and raphiophorids in the clastic facies were relatively abundant, but some endemic forms, such as the asaphid Birmanites and remopleuridid Hexacopyge, became dominant during the late Llanvirn-early Caradoc. Rorringtoniids are mainly associated with deeper outer-shelf facies. Panderia is common in an early Llanvirn nileid fauna at Yichongqiao, Cili area, and may well indicate development of shelf carbonate buildups. A transgressive event is suggested by the sudden appearance of rich Cyclopyge in the early Caradoc at Jiuxi, Changde.  相似文献   
3.
Rawdonia nasharae gen. et sp. nov. is described from the Carboniferous Carsonville and Berrico Creek Formations at Rawdon Vale, N.S.W. Rawdonia is distinguished from other athyridaceans by: the possession of a smooth brachial valve; a cardinal process which is rod-like, bordered by extensions of the socket plates, and has an alveolus or pit at the base; the lack of a cardinal plate; and the lack of well-defined dental plates. In New South Wales Rawdonia nasharae ranges from the Delepinea aspinosa Zone to the Rhipidomella fortimuscula Zone.  相似文献   
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