Dermatobranchus semilunus Gosliner & Fahey, 2011

Mehrotra, Rahul, A. Caballer Gutierrez, Manuel, M. Scott, Chad, Arnold, Spencer, Monchanin, Coline, Viyakarn, Voranop & Chavanich, Suchana, 2021, An updated inventory of sea slugs from Koh Tao, Thailand, with notes on their ecology and a dramatic biodiversity increase for Thai waters, ZooKeys 1042, pp. 73-188 : 73

* Dermatobranchus semilunus Gosliner & Fahey, 2011 Figure 19E

Material examined.

One specimen 33 mm, TB.

Ecology.

Exclusive to the soft sediment habitats outside the coral reef. Observed on Dendronephthya sp. octocoral, though active feeding was not observed. Depth 14-24 m.

Distribution.

Known from the West Pacific including Malaysia, the Philippines, Indonesia, and Papua New Guinea ( Gosliner and Fahey 2011). Here documented as a first record for Thai waters.

Remarks.

Specimens from Koh Tao are sometimes found with a pale yellow-pink margin to the oral veil. A similar trait is known from the closely related Dermatobranchus fasciatus Gosliner and Fahey 2011; however, the present specimens externally match D. semilunus based on other characteristics. Additionally, similar pigment appears to be visible in a photograph of a specimen in the original description of the species ( Gosliner and Fahey 2011: fig. 74C).

Figures

Figure 19. A Armina scotti 41 mm B Dermatobranchus caeruleomaculatus 55 mm C Dermatobranchus dendronephthyphagus 40 mm D Dermatobranchus fortunatus 11 mm E Dermatobranchus semilunus 33 mm (photograph by Pau Urgell Plaza) F Dermatobranchus cf. striatus 14 mm G, H Dermatobranchus sp. 1 32 mm (G) and 28 mm (H) I, J Dermatobranchus sp. 2 27 mm K Bornella hermanni 12 mm L Bornella johnsonorum 35 mm.