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. 6h): GS11148, J40/f8858, South Branch, Waihao River near Waihao Downs. Bortonian (GNS) |
Beu & Maxwell (1990): Chapter 7; p. 105; pl. 6 h.
Synonymy: Natica (Carinacca) allani Marwick 1924d, p. 554-555
Classification: Naticidae: Naticinae
Description: Size moderate for family (height 13-28 mm), ovate, spire about 0.25 height of shell, outline almost straight. Protoconch depressed, of about 3.5 smooth whorls. Teleoconch whorls gently convex, sutures only lightly impressed. Axial sculpture of growth lines only; spiral sculpture of very weak striae, most obvious just below suture. Inner lip almost straight, parietal callus thick with short entering ridge adapically, spreading down to coalesce with broad, low funicle near middle of lip. Outer lip strongly prosocline, inclined at about 25° from vertical. Umbilicus broad, bordered by a prominent ridge with a rounded outer edge and a sharp inner margin.
Comparison: Carinacca allani is very similar to C. waihaoensis (Pl. 8c), but is rather less globose and has a more elevated spire and a narrower umbilicus. The two forms overlap somewhat in stratigraphic range and possibly represent members of a gradually evolving lineage.
Carinacca is a relatively distinctive naticid genus characterised by the presence of a prominent circumumbilical ridge. It is recorded only from the Bortonian and Kaiatan in New Zealand, and is also present in the Middle Eocene of California (Marincovich 1977, p. 393).
Distribution: Bortonian-Kaiatan; Bortonian, Waihao Greensand, Waihao Downs (type); Kakahu; Bortons; Hampden Beach; Pareora River; McCulloch's Bridge. Common at type locality, uncommon to rare elsewhere.
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
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