New Zealand Journal of Geology and Geophysics abstracts
Chariocrinus (Crinoidea: Articulata) from the Latady Formation,
Behrendt and Hauberg Mountains, Ellsworth Land, Antarctica
Michael K. Eagle*
Daniel Hikuroa
Geology Department
University of Auckland
Private Bag 92 019
Auckland, New Zealand
email: m.eagle@auckland.ac.nz
and
*Department of Natural History
Auckland War Memorial Museum
Private Bag 92 018
Auckland, New Zealand
Abstract Specimens of a late Bajocian to early Callovian
isocrinid assigned to Pentacrinites cf. P. californicus (Clark),
and specimens collected by Hikuroa in 1999–2000, are described as a new species
of Chariocrinus. All specimens were collected from rock exposures
of the Latady Formation at eight localities in the Behrendt and Hauberg Mountains,
Ellsworth Land, Antarctica. The fauna, preserved in situ at all localities,
is essentially complete, but due to tectonism, localities may have been moved
many kilometres from their original position. Chariocrinus latadiensis
n. sp. is compared with congeneric species and those of Hispidocrinus.
It is the first record of the genus in the Southern Hemisphere, which has
European Tethyan affinities. Columnals are pentastellate to pentalobate,
and the symplectial articula appear diagnostic of Hispidocrinus but
are included in Chariocrinus on the basis of spineless axillaries
and fused adjacent crenulae; those of Hispidocrinus are spined and
separated by a furrow or smooth band, respectively. A single pluricolumnal
(?Apiocrinus) is the only associated crinoid found at any of the localities.
Chariocrinus latadiensis lived a semi-sessile existence on a volcarenite
substrate in association with vagrant ammonites, epifaunal and infaunal bivalves,
and epifaunal brachiopods. The benthic taxa lived in shallow, low energy
marine environments in the Middle Jurassic, part of a submarine back-arc
basin near the shore off southeastern Gondwana.
Keywords Crinoidea; Articulata; Isocrinida; Chariocrinus;
Antarctica; Ellsworth Land; Latady Formation; Behrendt Mountains; Middle
Jurassic; Chariocrinus latadiensis n. sp.; new taxonomic names
G02052; Received 30 September 2002; accepted 11 August 2003; online publication
date 13 November 2003
New Zealand Journal of Geology & Geophysics, 2003, Vol. 46: 529–537
0028–8306/03/4604–0529 $7.00/0 © The Royal Society of New Zealand
2003
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