title: A chancelloriid-like metazoan from the early Cambrian Chengjiang Lagerstätte, China.
abstract: Nidelric pugio gen. et sp. nov. from the Cambrian Series 2 Heilinpu Formation, Chengjiang Lagerstätte, 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.
authors.affiliation: Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China.
authors.forename: Xianguang
authors.initials: X
authors.lastname: Hou
authors.affiliation: Department of Geology, University of Leicester, Leicester LE1 7RH, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Williams
authors.affiliation: Department of Geology, University of Leicester, Leicester LE1 7RH, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Siveter
authors.affiliation: 1] Earth Collections, Oxford University Museum of Natural History, Parks Road, Oxford, OX1 3PW, UK [2] Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3PR, UK.
authors.forename: Derek J
authors.initials: DJ
authors.lastname: Siveter
authors.affiliation: Department of Geology, University of Leicester, Leicester LE1 7RH, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Gabbott
authors.affiliation: Department of Geology, University of Leicester, Leicester LE1 7RH, UK.
authors.forename: David
authors.initials: D
authors.lastname: Holwell
authors.affiliation: Department of Geology, University of Leicester, Leicester LE1 7RH, UK.
authors.forename: Thomas H P
authors.initials: TH
authors.lastname: Harvey
mesh_terms: D005580:Fossils; D010163:Paleontology