Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
| | Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
|
  (Pl. 37k): holotype, Waipipi Shellbeds, Waverley Beach, west of Wanganui, Waipipian (TM6821, GNS; origin unknown, ?ex Marshall and Murdoch Collection) |
Beu & Maxwell (1990): Chapter 14; p. 300; pl. 37 k.
Synonymy: Baryspira (Baryspira) oraria Olson 1956, p. 14
Classification: Olividae: Ancillinae
Description: Large for genus (54-57 mm high), tall and narrow, with spire half height of aperture; smooth except for basal spiral bands, growth lines on broad band, and very indistinct spiral ridges on spire. Outline strongly waisted at top of last whorl, with inflated, bullet-like spire and inflated last whorl with strongly convex outer lip. Spire callus descends last whorl to upper fifth of outer lip height. Parietal callus with lightly concave left outline over last whorl, extending back around quarter-whorl of spire as a strongly convex, thick "tongue"; weakly grooved up spire above posterior end of aperture. Broad band very wide; depressed band narrow, very distinct; top and mid-fasciolar bands (combined) equal in width to basal band. Columellar base with 4 weak plaits. Anterior of aperture wide, deeply notched.
Comparison: Amalda gulosa (Opoitian, southern Hawke's Bay) is shorter and still more inflated, and its parietal callus lacks the thick, convex, tongue-like margin of A. oraria, but the distinction is subtle and probably insignificant. The two (?) species differ from the Nukumaruan-Recent A. mucronata (Pl. 49g) in their marked waist at the top of the last whorl, below the spire. The relationship of these two (?) species to A. mucronata is unclear; specimens intermediate in size and shape between A. mucronata and A. tholiculus (type: Lillburnian, Island Creek, Waipaoa River, Gisborne district) occur commonly in shallow Kapitean-Waipipian facies from East Cape to Westland, but whether they evolved into A. mucronata is unclear.
Distribution: Waipipian (Opoitian?); Waipipi Shellbeds, Waverley Beach, west of Wanganui, Waipipian (type); common in shallow-water sandstone and shellbeds along the Wanganui-South Taranaki coast, but not known from elsewhere.
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
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)