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. 6p): holotype, Waihao Downs, South Canterbury, Bortonian (AMTM265, Auckland Museum) |
Beu & Maxwell (1990): Chapter 7; p. 109; pl. 6 p.
Synonymy: Eocithara (Marwickara) waihaoensis Laws 1935b, p. 29
Type species of Marwickara Laws, 1935
Classification: Harpidae: Harpinae
Description: Small for family (height 23 mm), elongate-ovate, spire 0.4 total height. Protoconch not definitely known. Teleoconch of 4 convex, weakly shouldered whorls, last whorl with a short neck; sutures impressed. Axial sculpture of narrow, sharp-crested costae with broad interspaces, opisthocyrt on spire, sinuous on last whorl, reaching across base; 20 on penultimate whorl. Spiral sculpture of fine cords between costae, intersected by growth lines. Aperture ovate, columella twisted to left at inception of short, open, shallowly notched siphonal canal. Inner lip narrowly but rather thickly callused, bearing a weak V-shaped parietal denticle. Outer lip sinuous with bevelled varix, weakly denticulate within. Fasciole moderately prominent, rounded.
Comparison: No other species of Eocithara have been described from New Zealand, but an as yet unnamed harpid from White's Creek, North Canterbury (Mangaorapan) probably belongs here; it differs from E. waihaoensis in its larger size (height 30 mm), lower spire, stronger spiral sculpture, and more prominent fasciole (Rehder 1973, p. 231). Another possible member of the genus is the very poorly preserved specimen from the Gisborne district (Duntroonian) that was originally identified as Morum (Oniscidia) sp. (Marwick 1931, p. 13, pl. 10, fig. 185; Fleming 1966b, pl. 113, fig. 1381). Until recently these were the only New Zealand species thought to belong in the warm-water family Harpidae, but it is now known that the genus Morum, long considered to be a cassid, is a harpid (Hughes 1986). Morum is represented in the Oligocene to Middle Miocene of New Zealand by at least three species of the subgenus Oniscidia (see below). Merle & Pacaud (2004) reconsidered the classification and phylogeny of fossil Harpinae, and retained Marwickara as a distinctive subgenus of Eocithara.
Distribution: Bortonian, Waihao Greensand, Waihao Downs, i.e. from South Branch, Waihao River (type) (very rare).
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
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ISSN 1177-2441
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