Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
(Pl. 1b): holotype, Wangaloa, Wangaloan (Otago University Geology Department) |
Beu & Maxwell (1990): Chapter 5; p. 77; pl. 1b
Synonymy: Malletia elongata Marshall 1917, p. 458; Neilo elongata; N. (Spineilo) elongata
Type species of Spineilo Finlay and Marwick, 1937
Classification: Malletiidae
Description: Size moderate for family (length 25-30 mm), elongate-ovate; anterior end rounded, posterior end produced, pointed; escutcheon lanceolate, slightly concave. Commarginal sculpture of fine, bevelled ridges; no radial sculpture. Hinge long, taxodont with numerous chevron-sectioned teeth, anterior and posterior series narrowing and meeting under beaks; no resilifer but dorsal margin of posterior series shallowly excavated over part of its length to accommodate external ligament. Adductor muscle scars small, subequal; pallial sinus moderately deep, rounded. Margins smooth.
Comparison: Spineilo elongata differs from species of Neilo (e.g. N. awamoana, Pl.16a, c) in its much more elongate shape and in its pointed rather than truncate posterior end. Puri (in Moore 1969, p. N235) synonymised Spineilo with Nuculana Link, 1807, but the absence of a resilifer and the presence of an external ligamental groove indicate that S. elongata is related to Neilo rather than to the Nuculanidae. Spineilo may be represented in the Late Cretaceous of Quiriquina, Chile by the species recorded as "Malletia pencana Phil, sp." by Wilckens (1904, p.230, pl. 19, fig. 6) (Marshall 1917, p. 459; Finlay & Marwick 1937, p. 17), although this does not seem to be conspecific with Neilo pencana (Philippi, 1887) which looks like a typical Neilo (Stinnesbeck 1986, p.166, pl. l, fig.12-14).
Distribution: Wangaloan, Wangaloa Formation, Wangaloa (type); Boulder Hill; lower Waihao River, South Canterbury (moderately common 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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