GNS Science

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

New Zealand Cenozoic Mollusca

Aethocola (Neocola) ngatuturaensis (Bartrum & Powell, 1928)


(Pl. 37l): GS8101, Y14/f7618, Oweka Creek, between Cape Runaway and Hick's Bay, East Cape, Opoitian (GNS)

Beu & Maxwell (1990): Chapter 14; p. 299; pl. 37 l.

Synonymy: Austrofusus (Neocola) ngatuturaensis Bartrum & Powell, 1928, p. 147.

Classification: Buccinulidae

Description: Small for genus (22-24 mm high), strongly biconic, spire slightly shorter than or equal to aperture and canal. Spire outline strongly stepped, with very prominently carinate shoulder angle, wide, shallowly concave sutural ramp, weak second angulation at top of aperture on last whorl, and last whorl contracting strongly over base to narrow neck and short, strongly twisted, narrow anterior canal with low fasciole bordered by a sharp, thin ridge. Sculpture of prominent, narrow spiral cords, 3 on spire whorls and about 8-9 on last whorl more prominent than the rest, with 1 narrow spiral thread in each of uppermost 3 interspaces and 4-5 threads on sutural ramp; crossing very prominent, narrowly rounded, moderately widely spaced axial costae that strengthen across ramp, form prominent, sharp nodules at shoulder angle, and die out below 4th prominent spiral cord on last whorl. Aperture large, with thin lips; inner lip smooth. Protoconch small, conical, of 3.5 smooth whorls, with a sharp apex.

Comparison: Aethocola ngatuturaensis is the culmination of the long-ranging mid-Cenozoic group of species (belonging in at least two lineages) included in A. (Neocola). All taxa are very useful in biostratigraphy, and the most important are described and illustrated here (A. alpha, Pl. 25b; A. beta, Pl. 25c; A. demissa, Pl. 30g; A. flexuosa, Pl. 25g; A. gamma, Pl. 25d). A. ngatuturaensis is distinguished from its presumed ancestor, A. gamma (= A. marwicki?), by having the prickliest and most prominent nodules and most prominent spiral cords of all A. (Neocola) species, although the distinction is subtle. We are not aware of Kapitean records of A. (Neocola). Adoption of Aethocola is discussed under A. acuticostata (Pl. 6m).

Distribution: Opoitian; Kaawa Creek, southwest Auckland (type); uncommon in shallow-water, soft-bottom facies (near-shore shellbeds to mid-shelf mudstone) at Kaawa Creek, at Oweka Creek near Cape Runaway, in the extensive Opoitian outcrops in the Tauwhareparae area inland from Tolaga Bay, and in the Kaniere district, Westland.

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