Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
(Pl. 26q): Tarakohe cement-works quarry, Takaka, northwest Nelson, Altonian (GNS, from a private collection; specimen with shell missing, showing sutures)
Beu & Maxwell (1990): Chapter 11; p. 239; pl. 26 q.
Synonymy: Nautilus cubaensis Lea 1841, p. 259; Aturia ziczac var. australis McCoy 1876, p. 21; A curvilineata Miller and Thompson 1937, p. 69; A. grangei Fleming 1945, p. 411; A. minoensis Kobayashi 1954b, p. 36
Description: Moderately large for genus (diameter 50-200 mm), shaped as in Nautilus (i.e. planispiral and completely involute) but narrower; last whorl completely enveloping preceding whorls, so previous whorl protrudes into base of last whorl to about lowest quarter of whorl height; centre of last whorl forming a small, pocket-like umbilicus on each side. Suture swinging strongly forward from umbilicus in a deep, regular arch occupying lower 0.67 of whorl, then backward to form a deep, narrow, pointed lateral lobe, visible on septal face as a very deep, narrow pocket on each side; suture then swinging strongly forward again to position of apex of curvature of previous suture on wide saddle below, where it turns abruptly at right angles to its previous course to pass straight across venter (without a ventral lobe). Septal face with a deep, narrow, conical hollow in mid-dorsal position, at exit of siphuncle; deeply concave above. Most specimens occurring as phragmocones only, i.e. lacking the body chamber. Exterior of complete shells smooth, polished, except for weak growth lines; sides almost flat, venter narrowly rounded.
Comparison: Jung (1966) pointed out that there are two widely distributed (cosmopolitan ?) Miocene species of Aturia A. aturi (Basterot, 1825) (type species of Aturia) with the septa weakly concave above the siphonal aperture, and A. cubaensis with the septa strongly concave above the siphonal aperture. He regarded A. australis as a synonym of A. cubaensis. Beu (1973a) noted that the common New Zealand Miocene Aturia is A. cubaensis, but that it is accompanied by a species with a deep V-shaped lobe at the summit of the ventral saddle: A. coxi Miller, 1947 (Clifdenian-Tongaporutuan). Both species occur widely, but in most places uncommonly, in shelf-facies sandstone and mudstone throughout New Zealand. To judge from modern Nautilus they were carnivores that swam near, but above, the substrate in tropical and subtropical regions (although dead shells float well, and some New Zealand specimens could have drifted from further north). The much larger (diameter up to 300 mm) A. mackayi (Dannevirke Series?; Bortonian-Kaiatan) appears to be related to the Northern Hemisphere A. ziczac (J. Sowerby, 1812). Another giant, unnamed species, at least 0.5 m in diameter, occurs in North Otago Oligocene rocks (Hamilton 1903; Hamilton's specimen from Wharekuri is in Otago Museum).
Distribution: Otaian?; Altonian-Kapitean; widespread but nowhere common in New Zealand (type of A. grangei from near Okahukura, Te Kuiti district, ?Waiauan- Tongaporutuan). Probably cosmopolitan.
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)