Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
(Pl. 9o), lectotype (TM2889, GNS); (Pl. 9n), possible syntype, GS329, G45/f8491, both from Pomahaka River, Duntroonian? (GNS) |
(Pl. 9p), lectotype (TM2889, GNS), GS329, G45/f8491, Pomahaka River, Duntroonian? (GNS) |
Beu & Maxwell (1990): Chapter 10; p. 139; pl. 9 n, o, p.
Synonymy: Chione accuminata Hutton 1873b, p. 21; C. (Hinemoana) acuminata
Type species of Hinemoana Marwick, 1927
Classification: Veneridae: Chioninae?
Description: Rather small for family (length 20-30 mm), ovate-trigonal, moderately inflated. Lunule not strongly differentiated, bounded by weak groove; escutcheon broad and flattened in left valve, scarcely defined on right. Commarginal sculpture of very fine, crowded, low, weakly frilled ridges; no definite radial sculpture, but subsurface radial elements revealed by weathering on some shells. Left hinge with short, narrowly triangular anterior cardinal tooth, a subrectangular, grooved median cardinal tooth, and a moderately long posterior cardinal tooth that is largely fused to nymph. Right hinge with a Very short, thin anterior cardinal tooth, a stout, grooved median cardinal tooth and a rather short, grooved posterior cardinal tooth; posterior lateral tooth distant, well developed, bounded above by groove to take projecting margin of left escutcheon. Pallial sinus very short, angular. Inner margins finely crenulate.
Comparison: Hinemoana acuminata resembles Austrovenus stutchburyi and other Austrovenus species in cardinal dentition and in the very short, angular pallial sinus, but differs in lacking definite radial sculpture and in having a distinct right posterior lateral tooth. This is the only known species of the genus. Austrovenus is first recorded from the Waitakian (Mataura River, near Brydone) and may have replaced Hinemoana ecologically. Beu (2004, p. 182) pointed out that Austrovenus is more nearly related to the South American genus Ameghinomya Ihering, 1907 than to Chione Megerle von Mühlfeld, 1811, and the subfamily classification of Hinemoana consequently is unclear at present.
Distribution: Duntroonian(?), Pomahaka Formation, Pomahaka River (type); Waikoikoi Stream. Locally abundant.
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
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