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. 37j): holotype, GS10192, CH/f105, Whenuataru Tuff, tip of Tarawhenua Peninsula, Pitt Island, Chatham Islands, Waipipian (TM6815, GNS) |
Beu & Maxwell (1990): Chapter 14; p. 298; pl. 37 j.
Synonymy: Ellicea (Pittella) valida Marwick 1928, p. 486
Type species of Pittella Marwick, 1928 (= Ellicea Finlay, 1928)
Classification: Buccinulidae
Description: Small for genus (37 mm high), very prominently sculptured, with short spire (half height of aperture and canal) and moderately long, widely open anterior canal, straight but deflected to left. Outline stepped, with prominent round shoulder at top of whorls, with evenly convex periphery and gently contracted base and neck. Sculpture of relatively few, wide, very prominent spiral cords, 5 on spire whorls and about 18 on last whorl and canal, becoming low and indistinct on canal; crossing (without forming nodules) prominent, narrowly rounded, widely spaced axial costae, extending from outer edge of sutural ramp to lower suture on spire whorls but only to periphery on last whorl. Aperture large, oval; outer lip thick, lirate within, with very thick posterior lip inside sutural ramp; inner lip thin posteriorly, with a single narrow parietal ridge, but thick anteriorly, bearing 8-10 low nodules on base of columella. Protoconch small, dome-shaped, of 2 smooth whorls.
Comparison: Aeneator validus differs from such typical mainland A. (Ellicea) species as the Pliocene A. orbitus and the living A. recens (Dell, 1956) only in its relatively wide sutural ramp; similarly prominent costae are seen on many specimens of A. orbitus. There seems little point in recognising subgenus Pittella, but we regard Ellicea as a useful subgenus for the deep-water Aeneator species with very prominent spiral cords. All species appear to have lived in the bathyal zone as noted under A. willetti (Pl. 27i), and in Pliocene rocks the presence of A. (Ellicea) is a primary bathyal indicator.
Distribution: Waipipian-Mangapanian; Whenuataru Tuff, northern Pitt Island, Chatham Islands (type), only known locality; rather rare. One of several bathyal indicators in the Whenuataru Tuff fauna (others are Coluzea aff. mariae, Galeodea triganceae, and Volutomitra banksi, specimen in Pl. 27k).
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
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