Biodiversity & Conservation

A sea slug - Onchidoris muricata

Onchidoris muricata

Image Jim Anderson - Onchidoris muricata. Image width ca 1cm.
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Distribution map

Onchidoris muricata recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

Why do the maps differ?

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Onchidoris muricata is not listed under any importance categories.

Taxonomy icon Taxonomy Taxon English term
Phylum Mollusca Snails, slugs, mussels, cockles, clams & squid
Class Gastropoda Snails, slugs & sea butterflies
Authority (O F Müller, 1776)
Recent synonyms None
Map icon Recorded Distribution in Britain and Ireland More common on the west coast of the British Isles particularly in the north. Few recordings on the east coast of the British Isles.
Habitat information icon Habitat information Onchidoris muricata is found on the lower shore or in sublittoral areas to depths of 15 m.
Text page icon Description Onchidoris muricata has a maximum length of 1.4 cm and is usually white in colour but pale yellow individuals have been recorded. Also some rare individuals have been recorded with brown speckling on the mantle. Club-shaped stalked projections (tubercles) are visible on its mantle. Up to 11 gills can also be found at the rear of the mantle. The head is extended to form an oral veil, which lacks tentacles. The eggs are spawned in a ribbon, coiled several times.
Identifying features
  • Grows up to 1.4 cm.
  • White or pale yellow in colour.
  • Rounded tubercles with flattened tops.
Additional information icon Additional information Likely to be confused with Adalaria proxima, however Onchidoris muricata has club-shaped tubercles whereas Adalaria proxima tentacles are pointed. Also Adalaria proxima is a large species, it can grow to 1.7 cm in length.

This review can be cited as follows:

Rose Edwards 2004. Onchidoris muricata. A sea slug. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 23/05/2013]. Available from: <http://www.marlin.ac.uk/speciesinformation.php?speciesID=3959>