A Revision of the Fossil and Living Gastropods Related to Plesiotriton Fischer, 1884 (Family Cancellariidae, Subfamily Plesiotritoninae n. subfam.), with an Appendix: Genera ofBuccinidae Pisaniinae Related to Colubraria Schumacher, 1817.

Submitted by Steve Wilkinson on
Reference

A. G. Beu and P. A. Maxwell. New Zealand Geological Survey Palaeontological Bulletin 54, 1987.

Review source

Originally reviewed by D.C. Long in 1989.
Published in Journal of Conchology (1989), Vol.33

This thorough review deals on a global basis with 7 genera of smallish ncogastropods - Turehua Marwick, 1943; Varicohilda Eames, 1957; Kapuatriton n.gen.: Plesiotriton Fischer, 1884; Africotriton n.gen.; Tritonoharpa Dall, 1908, and Loxotaphrus Harris, 1897. These range in age from the Late Cretaceous to the present day and, for the most part, were placed in the past in the Ranellidae. The authors assign them to the Cancellariidae and erect for them the new subfamily Plesiotritoninae, for which the principal taxonomic criterion is axial costae which are opisthocline and not collabral, a feature shown by no other Cancellariidae. Placement in the Cancellariidae is based on the similarity of the protoconch to that of other members of the family, the presence of columellar plaits in five of the genera, and the possession by Plesiotriton vivus Habc and Okutani, 1981 and Africotriton crebriliratus (G. B. Sowerby III, 1903) of a radula consisting of a single row of long, narrow, rachidian teeth. The radula, or lack of it, has apparently only been described for some 25 species of Cancellariidae, but a radula of this type appears to typify those cancellariids which have one. Though three of the genera of Plesiotritoninae are extinct and one, Tritonoharpa, lacks both radula and columellar plaits, it would be difficult not to accept the findings of the authors on the detailed evidence presented by them. My only point of curiosity is whether there really is no close connection between the Eocene Varicohilda turriculata (Newton, 1922) and the Recent Loxotaphrus deshayesii (Duval, 1841) both from West Africa.

The Bulletin includes a review of Semitriton Cossmann, 1903 and Tatara Fleming, 1950 and comments on Caveola Stcphenson, 1941 and Fusiaphera Habc 1961. These four genera are assigned to the Canccllariinac. The authors also remove a number of genera and spedes from the Ranellidac and Cancellariidae.

Finally, as the title indicates, an appendix lists and comments on the genera of Buccinidae, Pisaniinae, related to Colubraria - Fusus Helbling, 1779; Iredalula Finlay, 1926; Kaxamarua Kuroda, 1951 and Metula H. and A. Adams, 1853. The effect of this appendix is to propose that Cotubrariidae Dall, 1904 be no longer recognized as a separate family.

This works is very well produced and I was only able to spot one very minor typographical error. The illustrations are excellent and generally follow the order of the text but the only way back to the text from the plates is via the index, which could increase the wear on the publication.

The summary of the classification adopted on page 58 lists the new taxa and combinations proposed, including 19 new spedes.

It is thoroughly recommended, especially lor all institutional libraries and professional malacologists dealing with marine mollusca and for anyone interested in the Cancellariidae, and is obtainable from the New Zealand Geological Survey, P.O. Box 30-368, Lower Hutt, New Zealand.