Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
(Pl. 11d): GS9516, I40/f6675, Trig Z, Otiake, Waitakian (GNS) |
(Pl. 11f): GS9516, I40/f6675, Trig Z, Otiake, Waitakian (GNS) |
Beu & Maxwell (1990): Chapter 10; p. 150; pl. 11 d, f.
Synonymy: Chione vellicata Hutton 1873b, p. 21; C. meridionalis ("Sowerby") (not of G. B. Sowerby I, 1846); Cytherea (Circomphalus) chariessa Suter 1917, p. 74
Type species of Kuia Marwick, 1927
Classification: Veneridae: Venerinae
Description: Size moderate for subfamily (length 25-40 mm), suboval, moderately inflated. Lunule prominent, bounded by groove; escutcheon broad, more clearly differentiated in left than in right valve. Commarginal sculpture of thin lamellae of variable spacing, not persisting onto lunule or escutcheon. No radial sculpture, but subsurface radial elements visible on worn shells. Left hinge with a prominent anterior lateral tooth, a triangular anterior cardinal and a thin, slightly curved posterior cardinal partly fused to nymph. Right hinge with a deep anterior socket, a short, lamellar anterior cardinal tooth, a narrow median cardinal, and a very broad, deeply divided posterior cardinal. Pallial sinus moderately deep, acutely triangular, horizontal or somewhat ascending. Internal margins finely crenulate.
Comparison: Kuia vellicata is the most widely recorded venerid in mid-Cenozoic beds in the North Otago-South Canterbury area, and occurs in a wide range of lithofacies. It is particularly common at some localities (e.g. Trig Z and Target Gully Shellbed). The only other species of the genus so far described, K. macdowelli (Pl. 29f) is larger and has commarginal lamellae restricted to the early part of the shell, the remainder having grooves with distinctive, broad, smooth interspaces.
Distribution: Waitakian-Altonian; Mount Harris Formation, Awamoa, South Oamaru, Altonian (type locality of C. vellicata); Otekaike Limestone, Trig Z, Otiake, Waitakian (type locality of C. chariessa), and numerous localities in North Otago and South Canterbury. A juvenile shell from McCulloch's Bridge, Waihao River differs in only minor details from typical specimens, so the range may extend back to the Kaiatan.
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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