New data on the anatomy of fuxianhuiid arthropod Guangweicaris spinatus from the lower Cambrian Guanshan Biota, Yunnan, China

The fuxianhuiid arthropod Guangweicaris spinatus, from the lower Cambrian (Series 2, Stage 4), Guanshan Biota (Wulongqing Member, Canglangpu Formation), located in the vicinity of Kunming (Yunnan Province, southwest China), is redescribed based on new specimens and a re-examination of previously described material. A more complete overview of its morphology is given. Newly recognised features include: (i) a medial cephalic bulge; (ii) a tripartite hypostome; (iii) a pair of specialized post-antennal appendage (SPA); (iv) a putative telson; (v) two pairs of spines on the posteroventral margin of the terminal abdominal segment. This information is used to provide an emended diagnosis of the family Fuxianhuiidae, and the genus Guangweicaris.