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. 36p): Waipipi Shellbeds, Waverley Beach, west of Wanganui, Waipipian (GNS, ex Marshall and Murdoch Collection) (a weakly sculptured individual). |
Beu & Maxwell (1990): Chapter 14; p. 294; pl. 36 p.
Synonymy: Struthiolaria zelandiae Marshall and Murdoch 1920, p. 130
Classification: Struthiolariidae
Description: Moderately large for genus (36-50 mm high), with spire about equal to or slightly shorter than aperture, with a normal, wide Pelicaria aperture with weakly sinuous, varicate outer lip meeting thickened, smooth, narrow inner lip at shallow anterior notch; with an exceedingly deep, wide sutural channel (largest in genus). Whorls sloping inward above suture on spire to the marked subsutural carina, but vertical-sided on last whorl above a prominent protruding peribasal spiral cord (forming base of sutural channel on spire), then contracting rapidly below peribasal cord. Sculpture of narrow, prominent, vertical-sided, flat-topped spiral cords, exceedingly variable in number, prominence, and spacing; a few specimens have as few as 5 massive, wide cords above peribasal angle, but most have 6-8 narrow cords, and on many shells cords are very numerous, low, narrow and closely spaced above peribasal angle, producing a relatively smooth surface; all have 6 or 7 prominent basal cords; entire surface crowded with minute spiral threads; the only axial sculpture is faint, irregular growth lines. Protoconch irregular, paucispiral, normal for Pelicaria.
Comparison: The flat whorl sides, extremely prominent sutural channel, and relatively low spiral cords (apart from the prominent cord around the peribasal angle) lacking undercut sides distinguish Pelicaria zelandiae readily from P. canaliculata (Pl. 36q), with which it is sympatric at a few localities in the Waipipi Shellbeds. P. zelandiae is succeeded by P. granttaylori Beu, 2009, with a similar peribasal angle and sutural channel but a biangled upper whorl profile, in the Mangapanian and early Nukumaruan (Wilkies Shellbed, Hautawa Shellbed) of Wanganui basin and in the Mangapanian of northern Hawke's Bay (base of sand zone upstream from railway viaduct, Mohaka River).
Distribution: Opoitian?; Waipipian. Waipipi Shellbeds, Waverley Beach, west of Wanganui, Waipipian (type); common in Waipipian sandstone and shellbeds of shallow-water, soft-bottom facies along the Wanganui-South Taranaki coast; also rarely in Omihi Stream and nearby localities (Opoitian?; and in part Waipipian) in North Canterbury.
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)