Headshield Slugs; Cephalaspidea

The Headshield Slugs are a bunch of Opisthobranchs that spend more time under the sand than above. As a consequence they are not often spotted when SCUBA diving. Note the varieties of “headshield” front, used for cruising below the substrate.

The juveniles seem to have a darker colouration and a more simple patterning than the adults.

We thought it looked a bit like Philinopsis speciosa at first, but now we know that it is not.

Identifiable by the distinctive horizontal body stripes.

The headshield slug most often spotted when diving here. We have often seen them in large groups and even seen one swimming !

We first thought that this was T. lineolata until checking the photos after the dive...

Quite different from the Aglajids shown above, this Gastropterid moves surprisingly quickly (for its tiny size) over the sand.

This is a fairly obscure headshield slug, known as a bubble shell, due to its relatively large internal shell.