Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
(Pl. 36c): GS4949, N34/f6180, Lower Waipara Gorge near Greenwood's Bridge, North Canterbury, Waipipian (GNS) (a small but reasonably complete specimen). |
(Pl. 36g): GS4949, N34/f6180, Lower Waipara Gorge near Greenwood's Bridge, North Canterbury, Waipipian (GNS) (a small but reasonably complete specimen). |
Beu & Maxwell (1990): Chapter 14; p. 288; pl. 36 c,g.
Synonymy: Calliostoma waiparaense Suter 1917, p. 4; Maurea waiparaensis; Calliostoma (sensu lato) waiparaense, Beu & Maxwell 1990, p. 288, pl. 36c, g
Classification: Calliostomatidae
Description: The largest New Zealand fossil Calliostoma species (40-70 mm in diameter), with relatively low, stepped spire, strongly convex whorls, strongly rounded periphery, and weakly convex base. Sculpture of 3 prominent, wide, smooth, widely spaced spiral cords on first teleoconch whorl; number of cords increasing rapidly by intercalation of secondary and then tertiary cords, so 3rd and 4th whorls have 6 or 7 very prominent, wide, relatively coarsely beaded cords, and last whorl has 8-10 similar cords, all with wide, concave interspaces; on last whorl, a single narrow, smooth, low thread in the centre of each spiral interspace; cords become more numerous, smooth, and more closely spaced around periphery, to merge into 10 smooth, high, relatively closely spaced spiral cords on base. On some specimens, cords on base are beaded near periphery, and fine secondary threads occur between primary ones. Aperture oval, large; inner lip thick and wide, forming a pad over umbilicus. Protoconch not seen but presumably as in other Calliostoma species, very small, of 1 whorl with distinctive, prominent, honeycomb sculpture of narrow ridges.
Comparison: The similar but smaller, more finely sculptured form recorded as Calliostoma waiparaense from Nukumaru Brown Sand at Nukumaru Beach, Wanganui (Nukumaruan) by Beu (1973b, p. 320) is an unnamed species (pers. comm. B. A. Marshall, NMNZ). The rounded whorls and periphery and very coarse sculpture make C. waiparaense one of the most distinctive of our fossil Calliostoma species, certainly very different from the partly coeval, flat-sided species C. hawera.
Distribution: Waipipian; conglomeratic shellbeds in Greenwood Formation near Greenwood's Bridge, Lower Waipara Gorge, North Canterbury (type); not certainly known at any other locality, but common in several beds at the type locality.
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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