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. 6j): GS11150, J39/f7686, Pareora River near Mt Horrible, Bortonian (GNS) |
Beu & Maxwell (1990): Chapter 7; p. 106; pl. 6 j.
Synonymy: Priscoficus alectodens Marwick 1942, p. 275
Classification: Ficidae
Description: Size moderate for family (height 35-60 mm), pyriform, spire about 0.25 height. Protoconch apparently dome-shaped, of about 2.5 smooth whorls. Teleoconch of about 4 whorls, sharply shouldered above middle on spire; last whorl with 2 additional prominent keels, gradually contracted below to long, almost straight neck. Axial sculpture commencing as fine costellae reaching virtually from suture to suture but later becoming restricted to small, sharp tubercles on keels, those on shoulder keel stronger and less numerous than those below. Tubercles becoming less numerous on later whorls, c. 13-15 on shoulder keel of last whorl. Spiral sculpture of narrow, low cords with some interstitial threads. Aperture pyriform, constricted anteriorly to form siphonal canal. Inner lip with thin callus smear, outer lip thin, angled by keels.
Comparison: Priscoficus allani Marwick, 1960 (Mangaorapan, Otaio Gorge) was based on juvenile shells but seems to be very similar to P. alectodens and may not be distinct. P. obtusa (Pl. 2w) has clasping teleoconch whorls (i.e. the shoulder angle is obscured by the sutural ramp of the succeeding whorl) and has coarser tubercular sculpture and a more capacious aperture than P. alectodens.
Priscoficus differs from Ficus in having prominently keeled rather than evenly convex teleoconch whorls, and prominent nodular or tubercular sculpture in contrast to the predominantly spiral sculpture (and in some species fine axial sculpture) typical of the latter genus. Priscoficus is not known after the Bortonian in New Zealand; it is also recorded from Paleocene to Early Eocene in Europe and North America.
Distribution: Bortonian, Hampden Formation, Hampden Beach (type); Kakahu; Black Pt, Bortons; Ngapara; Pareora River. Rare at all 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
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