Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 21c): GS9685, J41/f9499B, Pukeuri road cutting, Oamaru, Altonian (GNS)
Beu & Maxwell (1990): Chapter 11; p. 200; pl. 21 c.
Synonymy: Cominula (Procominula) pukeuriensis Finlay 1926b, p. 242
Description: Small for genus (height 12-15 mm), elongate-ovate, spire 0.55-0.6 total height. Protoconch depressed-mamillate, of about 1.5 whorls, smooth or with a few weak axial costellae near end. Teleoconch of 4.5-5 whorls, convex at first but gradually becoming broadly angled near middle, sutural ramp slightly concave with a weak subsutural swelling. Last whorl gradually contracted to a short, ill-defined neck. Axial sculpture of prominent, narrow costae of rounded-triangular section with broad interspaces, reaching from suture to suture at first but then becoming obsolete on upper part of ramp, extending onto base of last whorl; 10-12 costae on penultimate whorl. Spiral sculpture of weak threads with narrow interspaces, 4 or 5 on base considerably stronger than others. Aperture ovate, columella almost straight and subvertical above, twisted to left below; siphonal canal short, twisted, strongly notched; fasciole not projecting, bounded above by sharp ridge. Inner lip moderately callused; outer lip thin, with 5 or 6 weak denticles within.
Comparison: Cominella pukeuriensis is distinguished from C. (Procominula) denselirata (Pl. 15j) by its taller spire (slightly more than half the total height, rather than less) and in having several basal spirals more prominent than the others. C. (Procominula) pulchra (Otaian, Bluecliffs and Pareora River) has spiral sculpture of prominent, crisp cords.
Distribution: Altonian; Mount Harris Formation, Pukeuri road cutting, Oamaru (type); Awamoa Creek; Old Rifle Butts, Cape Wanbrow; Target Gully Shellbed, Oamaru. Common at Pukeuri, less so 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
(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)