Gosliner & Fahey, 2008
Known only from Bali, Indonesia.
Upper: CASIZ 172860, Bali, Indonesia, 7 mm. Photo: M. Miller. Lower: CASIZ 172860. Radular morphology. Scale =10 µm.[From Gosliner & Fahey 2008: Fig. 24C].
The dorsum is lumpy, rather than smooth. The whole of the body is completely white, except for a thin dark brown ring about two-thirds of the way along the oral tentacles. From the photo it appears that in some of the 'pits' of the lumpy body, there may be translucent clear patches, but that is hard to determine.
One feature I am not sure about is Gosliner & Fahey's description of "two bifurcated extra-branchial appendages". A bifurcated extra-branchial appendage would be most unusual. I have only the photo to refer to and it appears from that, that there is a single extra-branchial appendage on each side which arises from the base of the lowest gill. Perhaps there is a lower branch of the extra-branchial appendage on each side, hidden from our view in the photo?
The animal is reported to grow to at least 7 mm in length.
Gosliner, T.M. & Fahey, S.H. (2008) Systematics of Trapania (Mollusca: Nudibranchia: Goniodorididae) with descriptions of 16 new species Systematics and Biodiversity, 6 (1): 53-98
Rudman, W.B., 2008 (March 10) Trapania armilla Gosliner & Fahey, 2008. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/traparmi