A chancelloriid-like metazoan from the early Cambrian Chengjiang Lagerstatte, China

作者:Hou Xianguang*; Williams Mark; Siveter David J; Siveter Derek J; Gabbott Sarah; Holwell David; Harvey Thomas H P
来源:Scientific Reports, 2014, 4(1): 7340.
DOI:10.1038/srep07340

摘要

Nidelric pugio gen. et sp. nov. from the Cambrian Series 2 Heilinpu Formation, Chengjiang Lagerstatte, Yunnan Province, China, is an ovoid, sac-like metazoan that bears single-element spines on its surface. N. pugio shows no trace of a gut, coelom, anterior differentiation, appendages, or internal organs that would suggest a bilateral body plan. Instead, the sac-like morphology invites comparison with the radially symmetrical chancelloriids. However, the single-element spines of N. pugio are atypical of the complex multi-element spine rosettes borne by most chancelloriids and N. pugio may signal the ancestral chancelloriid state, in which the spines had not yet fused. Alternatively, N. pugio may represent a group of radial metazoans that are discrete from chancelloriids. Whatever its precise phylogenetic position, N. pugio expands the known disparity of Cambrian scleritome-bearing animals, and provides a new model for reconstructing scleritomes from isolated microfossils.