Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 46e): GS4104, R22/f6518, basal shellbed member of Shakespeare Cliff Sand, Castlecliff, Wanganui, Castlecliffian (GNS)
(Pl. 46h): GS4104, R22/f6518, basal shellbed member of Shakespeare Cliff Sand, Castlecliff, Wanganui, Castlecliffian (GNS)
Beu & Maxwell (1990): Chapter 16; p. 344; pl. 46 e,h.
Synonymy: Venus intermedia Quoy & Gaimard 1835, p. 526, not of de Serres, 1829; Venus largillierti Philippi 1847, p. 87; Tapes intermedia; Tapes (Amygdala) intermedia; Paphia (Ruditapes) intermedia; Paphirus largillierti; Pullastra (Paphirus) largillierti; Venerupis (Paphirus) largillierti
Type species of Paphirus Finlay, 1926 (= Ruditapes Chiamenti, 1900)
Classification: Veneridae: Tapetinae
Description: Moderately large for genus (45-65 mm long), elongate and subrectangular, thick and solid, with smooth ventral margin. Umbones at anterior fifth of length; dorsal and ventral margins curved, subparallel; anterior and posterior margins nearly straight to lightly convex, converging towards dorsum. External sculpture of many low, wide, almost smooth, rather irregular, weakly anastomosing, commarginal costae, the postero-dorsal slope with about half the number of costae that are more prominent than on remainder of disc; all crossed by very fine, close, irregular commarginal ridges, and by rather stronger and more regular grooves on posterior area. Lunule concave, almost smooth, long and narrow, large for shell, weakly differentiated. Hinge with 3 narrow, cardinal teeth, only, in each valve; left posterior one lamellar, broken off most specimens; right anterior one low, lamellar; the other 2 in each valve medially grooved. Pallial sinus deep, oval.
Comparison: We agree with Fischer-Piette & Métivier (1971, p. 37) that Ruditapes largillierti belongs in Ruditapes Chiamenti, 1900; Suter (1913c, p. 995) also referred it to Ruditapes, as a subgenus of Paphia. Marwick (1927, p. 633) listed Tapes fabagella Deshayes, 1853 as a synonym of R. largillierti, and has been followed by all subsequent New Zealand authors, but Fischer-Piette & Métivier (1971, p. 9) listed it as a synonym of Venerupis anomala (Lamarck). Ruditapes largillierti is easily recognised by its elongate-subrectangular shape, its sculpture dominated by low, narrow radial ridges on the anterior three-quarters of the shell, and the low, sharp-edged commarginal ridges that dominate over the porterior dosal slope, and cross the radial ridges weakly over the rest of the shell. The hinge is narrow, with strongly subivided cardinal teeth. Young Recent specimens have a distinctive colour pattern of V-shaped markings.
Distribution: Waipipian-Recent; Recent, New Zealand (types of Venus intermedia and of V. largillierti). Abundant today in about 5 to 20 m, burrowing in muddy and sandy substrates in large, enclosed bays (i.e., in slightly lower than oceanic salinity, never in open-ocean situations) and so a rare fossil other than in some shallow-water beds at Castlecliff and in Haweran raised terrace faunas.
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
(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)