New Zealand Journal of Geology and Geophysics abstracts
Middle to Late Jurassic bivalves of the genera Neocrassina and Trigonopis
from New Zealand
Ronald N. Gardner
19B Cheam Street
Dallington
Christchurch, New Zealand
Hamish J. Campbell
Institute of Geological & Nuclear Sciences
P.O. Box 31 312
Lower Hutt, New Zealand
Abstract Bivalves of the genera Neocrassina and Trigonopis
are described from the Middle-Late Jurassic of New Zealand. Neocrassina is
represented by three new species. The new subfamily Trigonopinae is introduced
to accommodate the genus Trigonopis, which was previously classed as a subgenus
of Opis. Trigonopis is represented by one previously described species and
one new species. Paleobiogeography is analysed in terms of the global distribution
of Neocrassina and Trigonopis. Neocrassina was present in most regions of
the Boreal and Tethyan realms. In New Zealand, it is first recorded from
rocks of Early Temaikan age (Aalenian-Bajocian). The distribution of Trigonopis
shows that this genus was common in European Tethyan regions, but sparsely
distributed elsewhere. A comparison of New Zealand species, with forms from
other regions, demonstrates that Trigonopis most likely migrated to the Jurassic
southern ocean, by way of the temporary seaway connecting the Tethys Sea
with the Bay of Antarctica, during the Callovian marine transgression.
Keywords Antarctica; Astartidae; Astartinae; Australia;
Boreal; Jurassic; Murihiku Supergroup; Neocrassina; new taxa; New Zealand;
Opis; paleobiogeography; paleontology; Tethyan; Trigonopinae; Trigonopis
G01014 Received 24 May 2001; accepted 26 June 2002; published 27 September
2002
New Zealand Journal of Geology & Geophysics, 2002, Vol. 45: 323-347
0028-8306/02/4503-0323 $7.00/0 © The Royal Society of New Zealand
2002
PDF file of entire paper: Print-quality (4772K)
| screen-quality (560K)
This year's abstracts |
Journal home page |
All abstracts |
Publishing home page
