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. 22s): GS9500, J41/f8028, excavation for Oamaru Borough Council septic tank, South Oamaru, Altonian (GNS) |
Beu & Maxwell (1990): Chapter 11; p. 210; pl. 22 s.
Synonymy: Pleurotoma pagoda Hutton 1873b, p. 5 (not of Reeve, 1845); Pleurotoma alta Harris 1897, p. 45 (new name for Pleurotoma pagoda Hutton, 1873, preoccupied); Turris (Leucosyrinx) altus; Parasyrinx (Parasyrinx) alta, Beu & Maxwell 1990, p. 210, pl. 22s.
Type species of Parasyrinx Finlay, 1924
Classification: Turridae: Cochlepirinae
Description: Rather small for subfamily (height 20-25 mm), fusiform-biconic, spire pagodiform, 0.4 total height. Protoconch mamillate, of 1.5 smooth, convex whorls. Teleoconch of 5 or 6 whorls, sharply keeled at or below middle on spire, sutural ramp broad, almost flat, steep, sides sloping inwards. Last whorl with weak peribasal subangulation, strongly excavated below. No sculpture except for feeble spirals on neck of some shells. Aperture pyriform, columella almost straight, siphonal canal moderately long and narrow. Outer lip thin; anal sinus deeply arcuate, apex below middle of sutural ramp.
Comparison: Parasyrinx alta is distinguished from P. subalta (Pl. 15q) primarily by the total or near-total absence of spiral sculpture. A superficially similar, undescribed species occurring in the Mount Harris Formation at Bluecliffs, Otaio River and Pareora River (Otaian) differs from P. alta in having a more sharply projecting peripheral keel, a more prominent peribasal angulation, and distinct spiral sculpture on the base and neck. The Duntroonian-Waitakian P. subalta (Pl. 15q) is described above. Parasyrinx ranges from Kaiatan to Altonian. The former subgenus P. (Lirasyrinx) (Kaiatan to Duntroonian and possibly Waitakian) differs only in its taller, conical protoconch of 2.5 whorls, bearing fine spiral sculpture, but this developmental difference is no longer considered to separate genera. Hickman (1976, pp. 62-70) has referred several Paleogene turrids from the north-western USA to Parasyrinx.
Distribution: Altonian; Awamoa, Oamaru (type) and other localities in Mount Harris Formation, Oamaru district, moderately common at most localities.
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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