Austrodoris kerguelenensis from Antarctic waters

July 10, 2007
From: David Cothran

Hi Bill,
Here is a shot of Austrodoris kerguelenensis (or is it Doris now?) climbing on the solitary ascidian Cnemidocarpa verrucosa. Could it be grazing on the forams that often grow on this ascidian? I don't think that is could be feeding on the ascidian itself since this species has a very tough cuticle that contains cellulose. I have mostly seen A. kerguelenensis on the sponges Homaxinella balfourensis and Dendrilla antarctica. What do you think?

Locality: Port Lockroy (inner bay), Antarctic Peninsula, Southern Ocean. 16 meters, 12 cm long. 7 February 2007, Soft bottom, Photo: David Cothran

Best regards,

Cothran, D.B., 2007 (Jul 10) Austrodoris kerguelenensis from Antarctic waters. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear David,
Thanks for the photo. Concerning the status of Austrodoris - as I discussed in an earlier message [#19925 ], a new hypothesis has been made about the status of many dorid genera. The changes could all prove to be correct, but I don't think we should automatically accept every nomenclatural and taxonomic hypothesis as soon as it is proposed. In particular I would like to know what happens to the cladograms when multiple species of each genus are included.

Concerning feeding. I agree that it would be most unlikely that your animal is feeding on the ascidian or forams on the surface. As I mention on the Fact Sheet,  Barnes & Bullough (1996) report that it feeds almost exclusively on Dendrilla antarctica. Nudibranchs tend to perch in some strange places at times.

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Jul 10). Comment on Austrodoris kerguelenensis from Antarctic waters by David Cothran. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from