Known from Japan, Hong Kong, Queensland and New South Wales, so possibly has a wide western Pacific distribution.
Shelly Beach, Manly, Sydney, New South Wales, Australia, October 1984. 11mm long alive. PHOTO: Bill Rudman.
This species was described from a preserved animal and no information is available on the colour of the type specimen. However it has a unique shaped radular tooth which suggests that it can be identified with the animal illustrated here from Australia and from Hong Kong. Other similarly coloured species are Trapania darvelli which is white with brown gills, rhinophores, head tentacles and lateral processes and Trapania sp. illustrated here from Western Australia, which also has brown spots.
• Rudman,W.B. (1987) The genus Trapania (Nudibranchia: Goniodorididae) in the Indo-West Pacific. Journal of Molluscan Studies, 53: 189-212.
• Rudman, W.B. & Darvell, B.W. (1990) Opisthobranch molluscs of Hong Kong. Part 1. Goniodorididae, Onchidorididae, Triophidae, Gymnodorididae, Chromodorididae, (Nudibranchia). Asian Marine Biology, 7: 31-79
Rudman, W.B., 1998 (November 14) Trapania japonica (Baba, 1935). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/trapjapo