Nudibranch ID

Does anyone know what this Nudi is? My guess was a Phyllodesmium ... but not sure if this is right or what species.

Found at Jervis Bay, Weedy Valley, 15m.

cheers

Lndr

Yup, Phyllodesmium macphersonae. This one's especially neat because you can see the brown zooxanthellae through the skin. They come from the soft corals the nudi eats. The algae are somehow kept alive & transported to different spots in the body where they continue to produce nutrients which the nudi then uses.

Thanks Leslie. It wasn't close enough to the one on the sea slug forum for me to pick the species when I was trying to ID it. But delving further now it was interesting to read that the zooxanthellae are a distinguishing feature of this particular 'branch.

Attached is a close-up where backlighting really shows up the brown patches of zooxanthellae for anyone interested.

Lndr