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. 21k): GS9700, J38/f9681, Ardgowan Shellbed, Oamaru, Altonian (GNS) |
Beu & Maxwell (1990): Chapter 11; p. 197; pl. 21 k.
Synonymy: Aethocola spinifera Finlay and McDowall 1923, p. 113; Austrofusus (Austrofusus) spiniferus, Beu & Maxwell 1990, p. 197, pl. 21k.
Classification: Buccinulidae
Description: Moderately large for genus (height 40-55 mm), broadly bucciniform, spire 0.4-0.6 total height. Protoconch narrowly conical, of about 3 whorls, last half whorl with axial costellae, rest smooth. Teleoconch of 6-7 whorls, sharply shouldered at or below middle on spire, sutural ramp broad, steep, almost flat, sides sloping inwards. Last whorl with prominent peribasal angulation, space between it and shoulder angle concave; base almost flat, neck short, strongly twisted to left. Axial sculpture of prominent rounded costae reaching virtually from suture to suture on earliest whorls, but almost obsolete on ramp on later whorls and extending only a short distance below lower keel on last whorl, interspaces broadly concave. Costae slightly vertically compressed and subspinose on keels; 11-14 per whorl. Spiral sculpture of narrow cords with occasional interstitial threads, over whole surface except fasciole. Aperture ovate, columella concave above, twisted to left below to form short, strongly notched siphonal canal with prominent fasciole. Inner lip moderately callused; outer lip thin, finely lirate within.
Comparison: Aethocola spinifera is distinguished from most other species of Aethocola by its relatively large size, its broad shell and its strongly twisted neck. A. precursor (Duntroonian, Chatton and Wharekuri) is most similar, but differs in having much stronger spiral sculpture, particularly on the base. A. magnifica (Pl. 25a) (Altonian-Lillburnian, Clifden) is also closely related, but is larger and has the axial costae much more compressed and hence, more sharply spinose, on the keels.
Distribution: Altonian; Ardgowan Shellbed, Oamaru (type); Target Gully Shellbed; Awamoa Creek; Southburn Sand, White Rock River; Sutherlands; basal shellbed, Enys Formation, junction of Porter and Thomas River, Castle Hill Basin.
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
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