Trapania palmula
Gosliner & Fahey, 2008

Suborder: DORIDINA
Family: Goniodorididae


Known from Papua New Guinea, Indonesia and southern Japan.


Upper Right: Bali, Indonesia, 8 m, 24 Oct 2001., approx 6 mm long. Photo: Stuart Hutchison. Lower left: CASIZ 172856. Radular morphology. Scale =10 µm. [From Gosliner & Fahey, 2008: Fig 8C]. Lower right: CASIZ 083757, Philippine Islands, 5 mm. Photo: T. Gosliner.

The animal is translucent clear with patches of translucent brown. Scattered all over are small whitish spots and larger white spots on raised tubercles. In the specimen illustrated by Gosliner & Fahey [lower right photo] much of the dorsal surface has an opaque coating of light brown.

The anterior foot tentacles and the the oral tentacles are a translucent light brown with darker blotches and have a whitish base, then an irregular dark, almost black, band. The extra-rhinophoral and extra-branchial appendages have a light brown base and tip and in the midregion there is a white patch with a diagonal blue streak. The rhinophores and gills are translucent brown with whitish spots, much the same as the body.

The living animal is known to reach 6 mm in length.

This species was previously known on the Forum as Trapania sp. 5.

  • 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

Authorship details
Rudman, W.B., 2008 (March 10) Trapania palmula Gosliner & Fahey, 2008. [In] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

Feeding Trapania sp. from Bali

March 12, 2002
From: Stuart Hutchison

Note added 12 March 2008: This species has been named Trapania palmula.  

Here's a pair of unknown nudi's munching off a blue ascidian in Bali, Indonesia on 24 Oct 2001. You can see where they've been by the absence of 'tassles' on the eaten area. They were very small (approx 6mm long) and living at about 8m depth.

Hutchison, S., 2002 (Mar 12) Feeding Trapania sp. from Bali. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Thanks Stuart,
Another interesting find. This is almost certainly an unnamed species of Trapania. It is the only one I can think of with tubercles on its body. Of great interest are your photos of its feeding 'patch'. The 'tassles' you talk of are almost certainly a forest of entoprocts, the strange hydroid-like (though quite unrelated) animals which seem to be the sole food of species of Trapania. Entoprocts are sometimes called 'Moss Animals' which s very apropriate in this case.
Best wishes,
Bill Rudman

Rudman, W.B., 2002 (Mar 12). Comment on Feeding Trapania sp. from Bali by Stuart Hutchison. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from