GNS Science

Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)

New Zealand Cenozoic Mollusca

Parasyrinx subalta (Marshall & Murdoch, 1919)


(Pl. 15q): GS9517, I40/f9805, Campbell Park School, Otekaike Valley, Waitakian (GNS)

Beu & Maxwell (1990): Chapter 10; p. 162; pl. 15 q.

Synonymy: Leucosyrinx subaltus Marshall and Murdoch 1919, p. 256; Parasyrinx (Parasyrinx) subalta, Beu & Maxwell, 1990, p. 162, pl. 15q.

Classification: Turridae: Cochlespirinae?

Description: Size moderate for subfamily (height 17-32 mm), fusiform-pagodiform, spire about half total height. Protoconch bulbous, of 1.5 smooth whorls. Teleoconch whorls 7-8, sharply keeled at or below middle on spire; sutural ramp steep, slightly concave; sides sloping inwards. Last whorl with peribasal angulation, considerably weaker than peripheral keel, excavated below with a moderately long, almost straight neck. No axial sculpture; spiral sculpture of fine threads on lower part of sutural ramp and below peripheral keel, extending onto base and neck. Aperture pyriform, with a narrow, long, unnotched siphonal canal. Anal sinus deep, U-shaped, apex near middle of ramp.

Comparison: Parasyrinx subalta was probably ancestral to P. alta (Altonian; Pl. 22s), differing in having distinct spiral sculpture over most of the teleoconch rather than completely absent or confined to the lower part of the neck. P. anomala (Duntroonian, Wharekuri) has similar teleoconch sculpture to P. subalta but has a dome-shaped protoconch of about four whorls, the last two of which are spirally lirate.

Distribution: Duntroonian-Waitakian; Wharekuri Greensand, Wharekuri, Duntroonian (type); Otekaike Limestone, Trig Z, Otiake; Campbell Park School, Otekaike; Kyeburn district; Mount Harris Formation, upper Tengawai River. Rare in Wharekuri Greensand, but common at other localities.

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
(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)


Back to index page