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A late surviving xenopod (Arthropoda) from the Ordovican Period, Wales

Published online by Cambridge University Press:  19 June 2015

DAVID A. LEGG  and
THOMAS W. HEARING
DAVID A. LEGG*
Affiliation:
Oxford University Museum of Natural History, Parks Road, Oxford OX1 3PW, UK
THOMAS W. HEARING
Affiliation:
Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3PR, UK Current address: Department of Geology, University of Leicester, University Road, Leicester LE1 7RH, UK
*
†Author for correspondence: [email protected]
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Abstract

The Middle Ordovician Llanfallteg Formation has yielded remains of soft-bodied organisms previously known only from Cambrian Burgess Shale-type deposits. A new arthropod Etania howellsorum gen. et sp. nov. is described here, characterized by a semi-circular cephalon, clusters of spinose endites on the endopod and exopods with ovoid distal lobes. These characters are consistent with xenopod affinities, a clade otherwise known exclusively from the Cambrian Period. The discovery of E. howellsorum demonstrates that a number of Burgess Shale-type taxa, including xenopods, survived past the Cambrian Period (albeit within a restricted environment) and may have been outcompeted during the Great Ordovician Biodiversification Event (GOBE).

Keywords

EmeraldellaSidneyiaVicissicaudataCambrian faunaPalaeozoic fauna
Type
Rapid Communication
Information
Geological Magazine , Volume 152 , Issue 5 , September 2015 , pp. 942 - 948
Copyright
Copyright © Cambridge University Press 2015 

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