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The Early Cambrian trilobite Family Emuellidae Pocock, 1970: Systematic position and revision of Australian species

Published online by Cambridge University Press:  20 May 2016

John R. Paterson  and
Gregory D. Edgecombe
John R. Paterson
Affiliation:
Centre for Ecostratigraphy and Paleobiology, Department of Earth and Planetary Sciences, Macquarie University NSW 2109, Australia,
Gregory D. Edgecombe
Affiliation:
Australian Museum, 6 College Street, Sydney NSW 2010, Australia,
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Abstract

The family Emuellidae Pocock, 1970 was established for Emuella Pocock, 1970 and Balcoracania Pocock, 1970 from the Lower Cambrian of South Australia. Based on their peculiar trunk tagmosis, emuellids have been interpreted as the sister group of all other trilobites with dorsal facial sutures, and classified as high as the ordinal level. Cladistic analysis with a range of exemplar taxa of the Olenellina and Redlichiina instead resolves the emuellids within the Redlichiina, with tagmosis into a prothorax and opisthothorax (“telosoma”) nonhomologous in olenellines and emuellids. A taxonomic revision of Australian species identifies Balcoracania flindersi as a junior subjective synonym of B. dailyi, whereas the two named species of Emuella are considered to be distinct. Balcoracania dailyi possesses up to 103 thoracic segments, the maximum number recorded in any trilobite.

Type
Research Article
Information
Journal of Paleontology , Volume 80 , Issue 3 , May 2006 , pp. 496 - 513
Copyright
Copyright © The Paleontological Society 

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