Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
(Pl. 15s): GS9517, I40/f9805, Campbell Park School, Otekaike, Waitakian (GNS) |
Beu & Maxwell (1990): Chapter 10; p. 163; pl. 15 s.
Synonymy: Mangilia blandiata Suter 1917, p. 55
Classification: Turridae: Mitromorphinae
Description: Size moderate for subfamily (height 7-8 mm), elongate-ovate, spire 0.5-0.6 total height. Protoconch dome-shaped, of 1.2 whorls, smooth except for feeble axial costellae near end. Teleoconch of 4 whorls, weakly angled above middle on spire; sutural ramp strongly concave because of subsutural swelling, sides convex; last whorl weakly excavated. Axial sculpture of low, rather broadly rounded costae with broad, concave interspaces, almost obsolete on ramp, extending to lower suture on spire and dying out quickly on upper part of base of last whorl; becoming obsolete on later part of last whorl on some shells; 7-9 on penultimate whorl. Spiral sculpture very weak, of obscure threads and grooves, most prominent on base, and almost completely obsolete on some shells. Aperture ovate, columella smooth, bent to left anteriorly to form very short, unnotched siphonal canal. Outer lip thin, weakly flexuous, without a definite anal sinus.
Comparison: Scrinium blandiatum is distinguished from other New Zealand species of Scrinium by its small size, its strongly concave sutural ramp, its broadly rounded axial costae and its very feeble spiral sculpture. S. callimorphum (Duntroonian, Wharekuri) is considerably larger (height 16 mm) than S. blandiatum and has more prominent axial and spiral sculpture. Scrinium has a recorded range of Duntroonian to Recent in New Zealand and a similar range in Australia, but the Australian fossil species are only tentatively referred to the genus (Powell 1966, p. 67). Apart from the lack of columellar plaits, species such as S. blandiatum and S. callimorphum closely resemble species of Cordieria (Pl. 8m), a possible clue to their origin.
Distribution: Waitakian; Otekaike Limestone, Trig Z, Otiake (type); Campbell Park School, Otekaike (uncommon).
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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