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. 37s): holotype, GS4253, Q22/f7544, Upper Waipipi Shellbed, Waverley Beach, west of Wanganui, Waipipian (TM5092, GNS) |
Beu & Maxwell (1990): Chapter 14; p. 298; pl. 37 s.
Synonymy: Buccinulum(?) pangoides Beu 1973b, p. 323.
Classification: Buccinidae?
Description: Large for genus (50-62 mm high), weakly sculptured, tall and moderately narrow, with spire a little shorter than aperture and canal; canal moderately long, widely open, deflected weakly to left, with very weak fasciole. Whorl profile regularly convex from suture to base, except on last 0.5-1 whorl where it becomes concave over sutural ramp, producing a long, narrow, posterior apertural canal, unusual for genus. Sculpture of a few weak, indistinct spiral cords only, more obvious on neck than elsewhere. Outer lip thickened and lightly flared, with a row of about 16-18 low, narrow ridges inside. Inner lip thin, with single small, narrow, prominent parietal ridge, and 2-3 small nodules and single, narrow, prominent ridge on base of columella; columellar ridge formed on very low true spiral ridge at base of columella. Protoconch unknown.
Comparison: The taxonomic position of Buccinulum pangoides was uncertain until recently, as the protoconch is unknown, and the weak sculpture, narrow posterior apertural canal, thickened outer lip, and small but prominent, sharp parietal and columellar ridges are characters foreign to Buccinulum. However, Beu (2009) pointed out its similarity to Euthria Gray, 1850 (type species Murex corneus Linné, 1758, Pliocene to Recent, Mediterranean-S Portugal), and as Recent species of Euthria are now known from New Caledonia and Indonesia, regarded Euthria pangoides as a Pliocene immigrant down the Norfolk Ridge to New Zealand.
The specific epithet records the superficial similarity to Pangoa mira (Lillburnian, "Tutamoe conglomerate" in Pangopango Stream, inland from Tolaga Bay, north of Gisborne), a genus and species of mysterious affinities, based on a single severely abraded specimen. Pangoa mira has a shorter spire and very much more heavily thickened outer lip than those of B. pangoides.
Distribution: Waipipian; Upper Waipipi Shellbed, Waverley Beach, west of Wanganui (type), common in the basal sand member only; we have not seen specimens from any other locality. The shellbed was deposited on the inner shelf and represents a period of sediment-bypassing and shell concentration, but almost all taxa in the basal sandy member are soft-substrate, shelf species. Taxa present in the basal member include Coluzea, Murexsul, fairly common Scalptia haweraensis, and common Nassicola ultima, as well as E. pangoides and more common Waipipi taxa.
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)