Cart-Rut Shell Dicathais orbita

Form:

This is a large, solid, oval-shaped shell, with a short, low spire. The body whorl is very large and rounded.

In south-eastern Australia the sculpture consists of massive, deep, spiral ridges.

Across southern Australia the shell changes form from the deeply grooved eastern form to a smoother form across southern shores, to a tubercled and bumpy form in south-western Australia. See Biology below.

The mouth and operculum are oval. The columella is flattened. The siphonal canal is a short, broad notch.

Colour:

The shell is cream to white, with a white aperture, tinged yellow to orange near the lip. The end of the columella is yellow. The operculum is dark brown.

Distribution:

The Cart-Rut Shell and all of its forms range from southern Queensland, around the southern Australian shores to Barrow Island in Western Australia. Also New Zealand.

Habitat:

It occurs singly, or in small groups, in crevices and rock pools at mid to low-tide levels and below, often in regions of very strong wave action.

Biology:

This large carnivorous snail changes its form gradually over its distribution range across southern Australia. So much so, that previous researchers gave the forms three different scientific names. Click here to investigate this story.

References:

Bennett, I. (1987) W.J. Dakin's classic study: Australian Seashores. p.139, Angus & Robertson, Sydney.

Davey, K. (1998) A Photographic Guide to Seashore Life of Australia. p.24, New Holland, Sydney.

Edgar, G.J. (1997) Australian Marine Life: the plants and animals of temperate waters. p.46, Reed Books, Kew.

Womersley, H.B.S. (1987) The Marine Benthic Flora of Southern Australia. pt. 2 , p.194, South Australian Government Printer, Adelaide.

.

Molluscs
Murex Shells

Cart-Rut Shell
Mulberry Whelk

Home Page
Taxonomy
Biogeography
Rocky Shores
Tidal Levels
Intertidal Zonation
Environmental Factors
Biological Factors
Feeding Relationships
Activities
Glossary
References