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. 2j): GS10195, I44/f8486, Boulder Hill, Wangaloan (GNS) |
 (Pl. 2k): GS10195, I44/f8486, Boulder Hill, Wangaloan (GNS) |
Beu & Maxwell (1990): Chapter 5; p. 81; pl. 2 j, k.
Synonymy: Uber finlayi Marwick 1924d, p. 565; Polinella finlayi
Classification: Naticidae: Poliniceinae
Description: Size moderate for genus (height 25-45 mm), ovate or globose, spire low, pointed. Protoconch not distinguishable from teleoconch in available material, about 6 whorls in all, last strongly convex, capacious. No sculpture apart from growth lines. Aperture semicircular, inner lip almost straight except for shallow excavation near adapical end in most specimens. Inner-lip callus relatively narrow for genus, typically parallel-sided over most of its length, lacking definite transverse grooves, filling umbilicus completely in some shells, but leaving a shallow depression or groove in others. Outer lip slightly sinuous, strongly prosocline, inclined at about 35° from shell axis.
Comparison: Polinices (Polinella) finlayi differs from younger species of Polinices (Polinella) in having a much more strongly inclined outer lip and in lacking transverse grooves on the inner-lip callus. Except for a possible occurrence in the Late Cretaceous Quiriquina fauna of Chile, Polinella appears to be endemic to New Zealand, where it ranges from Wangaloan to Waipipian. Polinella is generally regarded as a subgenus of Polinices, differing from typical species of that taxon in having a much more restricted callus and, in most species, transverse grooves on the callus, although the difference is subtle. Polinella seems to have been bathymetrically more tolerant than Polinices (sensu stricto); the two taxa occur together in some shallow-water (inner or middle shelf) assemblages, but species of Polinella are more characteristic of outer shelf or upper bathyal sediments.
Distribution: Wangaloan, Boulder Hill (type); Wangaloa (common at both 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
(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)