Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
| | Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
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  (Pl. 40b): GS1820, U26/f6451, Castlepoint, west Wairarapa coast, Nukumaruan (GNS) |
 (Pl. 40f): GS1820, U26/f6451, Castlepoint, west Wairarapa coast, Nukumaruan (GNS) |
Beu & Maxwell (1990): Chapter 15; p. 310; pl. 40 b,f.
Synonymy: Talabrica senecta Powell 1931a, p. 109
Classification: Crassatellidae
Description: Small for family (15-19 mm long), weakly inflated, oval, with umbo central to slightly behind centre. Sculpture of even, relatively coarse, wide commarginal ridges with strongly convex cross-section and narrow interspaces. Interior of ventral margin smooth. Hinge deep and solid; umbonal region filled, not hollow. Tall, narrowly triangular, central resilifer is flanked on posterior by long, narrow, ligamental groove; and on anterior by 2 narrow, cardinal teeth and long, narrow, anterior lateral tooth on valve margin in right valve, and by 1 narrow cardinal tooth and 2 long, narrow, anterior lateral teeth in left valve. Adductor scars oval, almost equal; no pallial sinus.
Comparison: The living species Talabrica bellula (A. Adams) has weaker, rather irregular commarginal sculpture, whereas other named species (T. nummaria, Nukumaruan; T. inornata, Nukumaruan) have considerably weaker sculpture than T. bellula. However, the sculpture is variable within one species, and it is possible that T. nummaria and T. inornata intergrade with T. senecta. Early and middle Cenozoic Crassatellidae are much larger than Talabrica, and belong in Eucrassatella or Spissatella, except for the tiny (3-8 mm long) species of Salaputium.
Distribution: Mangapanian-Nukumaruan; Castlepoint, west Wairarapa coast, Nukumaruan (type), common; uncommon in shelf mudstone and muddy shellbeds in Wanganui basin and Wairarapa.
Cite this publication as: "A.G. Beu and J.I. Raine (2009). Revised
descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990). GNS
Science miscellaneous series no. 27."
© GNS Science, 2009
ISBN
978-0-478-19705-1
ISSN 1177-2441
(Included with a PDF facsimile file
copy of New Zealand Geological Survey Paleontological Bulletin 58 in CD version
from: Publications Officer, GNS Science, P.O. Box 30368 Lower Hutt, New
Zealand)