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. 8v): GS9508, J40/f8803, McCulloch's Bridge, Kaiatan (GNS) |
Beu & Maxwell (1990): Chapter 8; p. 125; pl. 8 v.
Synonymy: Daphnella (Raphitoma) neozelanica Suter 1917, p. 60; Belophos incertus Marshall 1919, p. 229
Type species of Marshallena Finlay in Allan, 1926
Classification: Turridae: Pseudotominae
Description: Size moderate for subfamily (height 18-25 mm), fusiform, spire about 0.4 total height. Protoconch conical, of about 5 convex whorls, last 0.25 whorl with distant, narrow axial costellae and very weak spirals, remainder smooth. Teleoconch of up to 4.5 whorls, shouldered a little above middle on spire; last whorl contracted gradually, broadly excavated, with a moderately long, narrow neck. Axial sculpture of narrow, sharp-crested costae reaching from suture to suture on spire and across base onto upper part of neck on last whorl; widely spaced on spire whorls, but more crowded and less distinct on last half-whorl; 20-27 on penultimate whorl. Spiral sculpture of low, narrow cords, the strongest on shoulder angle, those on whorl sides stronger than those on ramp and all less prominent than axial costae. Cord on shoulder angle weakly tuberculate at intersections with costae, other spirals crossing axials unchanged. Well preserved shells with a slightly glazed overall appearance. Aperture pyriform, with a moderately long, slightly curved, narrow, unnotched siphonal canal. Inner lip distinctly impressed; outer lip thin with a shallowly arcuate sinus on ramp.
Comparison: Marshallena neozelanica is distinguished from other New Zealand turrids by its almost smooth conical protoconch, its moderately long siphonal canal, its fine spiral sculpture and its very shallow anal sinus. Although several other New Zealand turrids have been assigned to Marshallena, most belong in Zeatoma Maxwell, 1992, and only M. curtata (Pl. 27r) is considered to be congeneric with M. neozelanica. M. curtata differs from M. neozelanica in being less elongate, having more strongly shouldered teleoconch whorls and having more prominent axial sculpture.
Marshallena seems to be extinct in the New Zealand region, but it is represented in the modern Indo-Pacific fauna by several species from mid-shelf to bathyal habitats (Powell 1969). The few New Zealand records of the genus are from outer-shelf or upper bathyal assemblages.
Distribution: Bortonian-Kaiatan; Bortonian?, "Teaneraki" (type locality of Daphnella neozelanica - probably lower Waihao River); Bortonian, Hampden Formation, Hampden Beach (type locality of B. incertus) (rare); Waihao Greensand, McCulloch's Bridge (moderately common).
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)