Chengjiang Fauna Brachiopods,

Since 1991, morphological and ecological investigation of the brachiopods in the Early Cambrian Chengjiang Lagerstatte has been done extensively and intensively. Based on a huge number of bachiopod fossils recently collected from Haikou, Kunming, the 5 known taxa of brachiopods in Chengjiang fauna are further researched into and a new lingulid genus and a new species (Xianshanella haikouensis gen. et sp.nov.) is erected herein. A study of these brachiopod fossils demonstrates that the Chengjiang Lagerstatte has the potential to elucidate the character acquisition and character evolution of brachiopod in the early Cambrian and to explore the earliest Phanerozoic diversification of Brachiopoda.Based on close examination and detailed anatomy of thousands of specimens, much new information pertaining to the 5 known taxa of brachiopods has been revealed here.1) The U-shaped digestive canals with an anterior anus in lingulids are revealed.2) The early spirolophe composed of two spiral brachial arms distinctly preserved, with delicate tentacles, turn up in the Lingulepis malongensis.3) The early Cambrian lingulids from the Chengjiang fauna could not only live buried in the sediment, but also could locomote on the bottomof sea with the pedicle functioned for drive through its crimping and stretching.4) Based on several exceptionally preserved fossils, it is proposed that water enter into the valves laterally and exit anteriorly in early Cambrian lingulid brachiopods.5) The lophophores at trocholophe stage in Heliomedusa orienta are tentatively interpreted here.6) The mineralization of the animal took place gradually from outside to inside during their preservation before the fresh carcass were broken down, which could have given access to the preservation of the softy anatomy of organisms in Chengjiang fauna.