* Trapania cf. gibbera Gosliner & Fahey, 2008 Figure 13L

Material examined.

One specimen 5 mm, CB.

Ecology.

Under rubble in shallow coral reefs. Depth 4-6 m.

Distribution.

Trapania gibbera is known from Indonesia, Japan, and Papua New Guinea (Gosliner and Fahey 2008). Here representing a first record for Thai waters.

Remarks.

Specimens from Koh Tao differ slightly from Trapania gibbera Gosliner and Fahey 2008 in colouration. The ‘hump’ located anterior to the gills, for which T. gibbera was named, is also seen in specimens from Koh Tao. The dorsal colouration is tan rather than white with numerous reddish brown patches spread over the body, sometimes giving animals a reticulated appearance. Rhinophore clubs have nine lamellae that are mostly white with some edges being red, with translucent red stalks and red apices. A deep red mark can be seen at the anterior margin of the head that extends to the oral tentacles, which turn orange-brown and have a single distinctive white spot on the dorsal surface of each. Ventrally the oral tentacles are entirely orange.