February 6, 2009
From: Sully Bachel
Concerning message #3828:
My wife Monika found this nudibranch on a sandy rock. It was quite difficult to see it because of the colour and its small size.
It is probably a Thuridilla or a Elysia.
What is your opinion
Locality: La Possession, 6 m, Reunion Island, Indian Ocean, 28 December 2008. Length: 15 mm. Photographer: Sully Bachel.
Thanks for your identification
firstname.lastname@example.orgBachel, S., 2009 (Feb 6) Re: Thuridilla kathae? from Reunion Is.. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22211
It is certainly and Elysia or a Thuridilla. One way the genera can be distinguished externally - in most cases - is that in Thuridilla there is usually a bright colour pattern, the pigments being quite opaque, while in Elysia, there may be colourful markings but the background colour is usually translucent with the green of the branching internal digestive gland showing through. Certainly the row of raised white spots along each side of the parapodia are similar to Thuridlla kathae, the translucent body through which we can see green digestive gland branching, is unusual.
I would be grateful for some guidance from Kathe Jensen or Terry Gosliner