Soft-tissue preservation in the Lower Cambrian linguloid brachiopod from South China

摘要: The organization of the lophophore and digestive system are recognized as two diagnostic characters in defi− nition higher brachiopod taxa, hence play a major role their phylogenetic analysis, structure, however, is very rarely fossilized. Here we describe interpret specimens Lingulellotreta malongensis, from Lower Cambrian Chengjiang Lagerstatte (South China), one earliest known taxa Lingulellotretidae, which lophophores intact, U−shaped tracts extraordinarily well−preserved. lophophore, with clearly pre− served tentacles, corresponds to an early spirolophe developmental stage. tract consists mouth, esopha− gus, distended stomach, intestine anterior anus, differs that obolid Lingulella chengjiangensis by presence dilated stomach absence looped Lingula. In addition, relative sizes mantle visceral cavities malongensis also described. These fossils dem− onstrate Atdabanian brachiopods had already possessed advanced features, suggest anus plesiomorphies.