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. 36q): Lower Awatere Valley, Marlborough (almost certainly from Starborough Creek), Waipipian (GNS, ex Marshall and Murdoch Collection) |
Beu & Maxwell (1990): Chapter 14; p. 293; pl. 36 q.
Synonymy: Struthiolaria canaliculata Zittel 1864, p. 34; Pelicaria canaliculata becki Neef 1970, p. 469
Classification: Struthiolariidae
Description: Large for genus (38-55 mm high), with moderately tall spire (slightly shorter than to slightly taller than aperture), with a deep, narrow sutural channel, evenly and strongly convex to slightly quadrate whorls, and normal Pelicaria aperture with weakly sinuous, varicate outer lip meeting thickened, smooth, narrow inner lip at shallow anterior notch. Sculpture of exceedingly prominent, wide, high spiral cords with weakly convex tops and deeply undercut edges, 3-4 on spire whorls and 8 on last whorl, very obscurely nodulous at the shoulder in some specimens; the whole surface closely crowded with fine spiral threads. Protoconch irregular, paucispiral, normal for subgenus.
Comparison: Pelicaria canaliculata is highly variable in form; very inflated specimens with relatively low cords occur in some populations, and Neef (1970) regarded these as "typical" P. canaliculata, and named narrow, prominently carinate specimens as P. canaliculata becki. However, the two are extremes of one intergrading population. Neef (1970) described a sequence at Mangahao, northern Wairarapa, where P. canaliculata evolved progressively (anageneticaly?) into the early P. acuminata form of P. vermis (late Mangapanian-early Nukumaruan; Pl. 42e); intermediate species are P. clarki (early Mangapanian; lower cords than in P. canaliculata, with vertical sides) and P. marima (mid-Mangapanian; still lower cords). An apparently ancestral species, P. procanalis (Opoitian, mouth of Upton Brook, Awatere Valley) has much lower, wider and closer spiral cords than P. canaliculata.
Distribution: Waipipian; Awatere Valley, Marlborough (type), almost certainly from the Starborough Formation in Starborough Creek, near the present town of Seddon, where the species is common. Common also at the mouth of Blind River, Awatere, and in the Mangahao district west of Pahiatua, northern Wairarapa; also occurs rarely in the Waipipi shellbeds at Waverley Beach, west of Wanganui.
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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