The Palaeobiology of Two Crown Group Cnidarians: <i>Haootia quadriformis</i> and <i>Mamsetia manunis</i> gen. et sp. nov. from the Ediacaran of Newfoundland, Canada
D. McIlroy,
G. Pasinetti,
D. Pérez-Pinedo,
C. McKean,
S. C. Dufour,
J. J. Matthews,
L. R. Menon,
R. Nicholls,
R. S. Taylor
Affiliations
D. McIlroy
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
G. Pasinetti
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
D. Pérez-Pinedo
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
C. McKean
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
S. C. Dufour
Department of Biology, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
J. J. Matthews
Museum of Natural History, University of Oxford, Oxford OX3 7DQ, UK
L. R. Menon
Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK
R. Nicholls
BobNichollsArt, Bristol BS161QY, UK
R. S. Taylor
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
The Ediacaran of eastern Newfoundland preserves the world’s oldest known eumetazoan body fossils, as well as the earliest known record of fossilized muscular tissue. Re-examination of the holotype of the eight-armed Haootia quadriformis in terms of its morphology, the arrangement of its muscle filament bundles, and hitherto undescribed aspects of its anatomy support its interpretation as a crown staurozoan. We also document several new fossils preserving muscle tissue with a different muscular architecture to Haootia, but with only four arms. This new material allows us to describe a new crown group staurozoan, Mamsetia manunis gen. et sp. nov. This work confirms the presence of crown group medusozoan cnidarians of the Staurozoa in the Ediacaran of Newfoundland circa 565 Ma.
