First occurrence of a new Ocruranus-like helcionelloid mollusc from the lower Cambrian of East Gondwana

• Published in: Gondwana Research
• Main Authors: Skovsted, Christian, Brock, Glenn A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Enheten för paleobiologi 2012
• Subjects: Emargimantus; Helcionelloida; Ocruranus; Lower Cambrian; Gondwana; Geology; Geologi; Greenland; East Greenland
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-874; https://doi.org/10.1016/j.gr.2011.09.003

A new cap-shaped mollusc, Emargimantus angulatus gen. et sp. nov. is described from the Arrowie Basin of South Australia. The new species is closely comparable to mollusc species from South China and North-East Greenland previously described under the generic name Ocruranus Liu, a genus recently reinterpreted as a multiplated, possibly polyplacophoran mollusc. Emargimantus is interpreted as a univalved helcionelloid mollusc and differs from Ocruranus in both morphology and function. E. angulatus represents the first discovery of Ocruranus-like helcionelloids in the lower Cambrian of eastern Gondwana and demonstrates that these molluscs had a global distribution during the early Cambrian. Origin and early evolution of major animal clades in the Cambrian Period