A rather small Aeolid Nudibranch.

Our commonest Facelinid nudibranch, if that is what you call them. Small and quite fast moving. Used to be in the genus Phidiana...

Only two sightings so far; thank you to Mr Lorenzo for the ID.

Another case of taking a photo because it looked like there might be something there. Shame I took no more.

Young ones are quite similar in appearance to Carolia indica, at first sight.

They live on Sinularia soft corals and use their chloroplasts to photosynthesize energy for themselves!