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. 56i): Ringicula (Ringicula) castigata Marwick, 1929; topotype, GS9806, J45/f9668, Shell Gully, Chatton, Southland (Duntroonian) (apex showing protoconch with partly immersed initial whorl). |
  (Pl. 56j): Ringicula (Ringicula) castigata Marwick, 1929; topotype, GS9806, J45/f9668, Shell Gully, Chatton, Southland (Duntroonian) |
Beu & Maxwell (1990): Chapter 17; p. 386; pl. 56 i,j.
Classification: Ringiculidae
Description: Height 1.5-4.9 mm, elongate-ovate, spire moderately elevated. Protoconch narrowly dome-shaped, smooth, with small, slightly immersed initial whorl. Teleoconch whorls convex, last whorl large, strongly convex; sculpture of incised spiral grooves. Aperture constricted posteriorly, with a shallow, strongly oblique channel immediately below columella. Columella short, bearing 2 strong plaits; some species with a prominent parietal plait as well. Outer lip thickened, smooth in some species, finely denticulate over its length or with a single strong denticle near middle in others.
Comparison: Two major groups are represented in New Zealand — in one group (referred to Ringicula (sensu stricto)) there is a prominent parietal plait, and the outer lip typically bears a single strong denticle; in the other (subgenus Ringiculina Monterosato, 1884) the parietal plait is obsolete and the outer lip is smooth and typically thinner than in Ringicula (sensu stricto) (Maxwell 1988a, p. 75). The only described modern species from New Zealand, R. delecta Murdoch & Suter, 1906, belongs in R. (Ringiculina). Several other genera of Late Cretaceous-early Cenozoic ringulids reach a much larger adult size and are shorter, subspherical shells.
Distribution: Mangaorapan-Recent, New Zealand; cosmopolitan, recorded from Late Cretaceous-Recent and from a wide range of depths.
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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