Spurilla major from Turkey

Dear Tom,

This is a member of the Aeolidiidae so its closeness to a sea anemone could suggest it was looking for food. I am pretty sure this is the Indo-West Pacific species Spurilla major. It probably keeps zooxanthellae alive in its body so it usually has a dark brown background colour and duller colour pattern on its skin but Eliot did describe a bright colour variety as 'var ornata'. I suspect your animal is this bright colour form and far from it being a colour variant I suspect it is a result of the brown zooxanthellae normally found in the branching digestive gland throughout the body wall being absent. If you look at the close-up alongside, you can see in the ceras just behind the rhinophores a dull brown duct with short branches. That is the digestive gland and I suspect the shortened side branches indicates the animal has not fed on sea anemones with appropriate zooxanthellae for a while. You get a similar change in colour in Spurilla australis - see Fact Sheet.

I presume this is one of the species you though might be a lessepsisan migrant from the Indian Ocean. If so, I fully agree.

Best wishes,
Bill Rudman