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Family  Plesiotrochidae





The Plesiotrochidae is a family of about 11 species, found in both tropical and temperate seas. There are 8 species recognised from Australia, 3 of which are from southern Australia and the rest from the tropical Indo-West Pacific region.

The family was named in1990 by Richard Houbrick, who placed it in the superfamily Cerithioidea. A later study of the sperm structure by John Healy (1993) showed that it was better placed in the superfamily Campaniloidea, alongside the Campanilidae. Houbrick described the anatomy, radula and reproduction of one south-western Australian species, which he referred to as Plesiotrochus cf. penitricincta Cotton, 1932 (later identified as Plesiotrochus crinitis Thiele, 1930). He found it to be a simultaneous hermaphrodite, feeding on algae.

Members of the family appear to occupy different habitats. The species studied by Houbrick lives on algal fronds in shallow intertidal pools, as does Plesiotrochus monachus in southern Australia, but at least some of the tropical species occur on coral reefs.

The only species of the family known from NSW is Plesiotrochus monachus (Crosse & Fischer, 1864). This has a southern Australian distribution; in NSW it occurs only in the far south.

Family Reference

Houbrick, R.S. 1990. Aspects of the anatomy of Plesiotrochus (Plesiotrochidae, fam. n.) and its systematic position in Cerithioidea (Prosobranchia Caenogastropoda). In, Wells, F.E., Walker, D.I., Kirkman, H. & Lethbridge, R. (eds). Proceedings of the Third International Marine Biological Workshop: The Marine Flora and Fauna of Albany, Western Australia. Perth : Western Australia Museum. Volume 1.


The only species of the family known from NSW is detailed here. Jansen (1995) listed Plesiotrochus pagodiformis Hedley, 1907 from NSW, but that record cannot be confirmed.

Identification Notes

Shells small to medium in size, with strongly angled whorls, aperture with anterior canal.


Copyright Des Beechey 2014