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. 41l): GS10849, V20/f8572, Devil's Elbow mudstone, near top of Devil's Elbow hill, Napier- Wairoa highway, Nukumaruan (GNS) |
Beu & Maxwell (1990): Chapter 15; p. 317; pl. 41 l.
Synonymy: Dentalium nanum Hutton 1873b, p. 1; D. huttoni Kirk 1880, p. 306; D. marwicki Mestayer 1926, p. 587; Dentalium (Antalis) nanum
Classification: Dentaliidae
Description: Small for genus (15-37 mm long), most specimens around 20-25 mm long at maturity; tubular, narrow, gently tapered to a narrow apex, and lightly curved; open at both ends. Sculpture of simple, low, narrow-crested, longitudinal costae with shallowly concave interspaces; number of costae varying from 6 to 13, but most specimens having 8 or 9, and so roughly octagonal in section.
Comparison: The much larger species (60-100 mm long) Fissidentalium zelandicum, common in Kapitean-Recent offshore facies, has coarser and much more numerous longitudinal costae than Antalis nana, and has a deep slit in the apical end. The only other moderately large scaphopod common in Pliocene rocks is Antalis pareorensis (Kapitean-Waipipian), a large, very gently tapered, almost smooth species (typical Pliocene specimens have fine longitudinal costae near the apex).
Distribution: Altonian(?)-Recent. Shakespeare Cliff, Wanganui, Castlecliffian (type of D. nanum; Recent, New Zealand, "from the stomach of a trumpeter (Latris hecateia)" (type of D. huttoni); Castlecliff, Wanganui, "lower bed", Castlecliffian (type of D. marwicki). Abundant today buried with only the narrower apex protruding from soft substrates in shallow to moderately deep water (15-300 m; as shallow as 5 m or less in a few sheltered environments such as Orua Bay, Manukau Harbour) all around New Zealand; equally common in most New Zealand Pliocene and Pleistocene fine-grained rocks that were deposited in this depth range; superficially similar specimens occur at Ardgowan and Target Gully, Oamaru (Altonian) but may not be conspecific.
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)