June 5, 2009
From: Patrick Aristobil-Adele
Concerning message #22495:
I found this nudibranch at the Pipeline in Nelson Bay. It was crawling fairly rapidly across the sand but gave me enough time to take a few snapshots.
I am new to the forum and to underwater photography however I am developing a keen interest in marine species such as nudibranchs. I was encouraged to post this message by David and Leanne Atkinson who have been an invaluable help in teaching me how to locate small marine organisms and how to photograph them.
I would like to know if this particular Cerberilla sp. has been photographed in New South Wales before.
Locality: Nelson Bay, 6m, NSW, Australia, Pacific, 08 February 2009, Sandy Bottom. Length: Approx. 4 mm - 5 mm. Photographer: Patrick Aristobil-Adele.
Aristobil-Adele, P.J., 2009 (Jun 5) Re: Cerberilla sp 8. from Arabian Sea. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22522
I am glad the Atkinson's encouraged you to send these photos, because it is an interesting find. Cerberilla sp. 8 has possibly been photographed in New South Wales, or some other part of Australia before, but I am not aware of it. I have found it in New Caledonia, and as you know, we have a recent record from the Arabian Sea. I am beginning to wonder whether this is a colourful form of Cerberilla incola which is know only from southeastern Australia and is rather a dull coloured, quite small species. I noticed in your animal that the cerata have a black band along each edge of the cerata, just as in C. incola. Perhaps that species is a juvenile of your much more colourful animal.
Over the years, numbers of Cerberilla incola - always small - have turned up in samples taken by ecologists from various bays and harbours along the coast of New South Wales. Perhaps they are juveniles which have settled from plankton drifting down from warmer waters? I guess what we will need to do is try and find some smaller Cerberilla sp. 8, or larger C. incola to see if we can find some intermediate colour forms. As I have said before, we know very little about most species of Cerberilla because they spend most of their life hidden in the sand.