Cerberilla cf. incola Burn, 1974

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

* Cerberilla cf. incola Burn, 1974 Figure 17F, G

Material examined.

Two specimens 7-12 mm, TT.

Ecology.

Exclusively found in deeper soft sediment habitats outside coral reef habitats, where it exhibits an endo-benthic substrate preference. Depth 14-20 m.

Distribution.

Cerberilla incola is known from Australia ( Burn 1974) and Réunion Island ( Bachel 2010). First documented from the Gulf of Thailand by Chavanich et al. (2013).

Remarks.

Cerberilla incola as described by Burn (1974) represents a largely brown animal with dark brown rhinophores, dark brown lines across oral tentacles and along lateral and central lines of the dorsum with central cerata tipped with dark arrow-shaped marks. A later observation from near the type locality of South-East Australia ( Cobb 2010) highlighted a light brown to nearly white specimen with pale blue lines along oral tentacles, a distinctive yellow-orange band along the anterior portion of the head, and with most cerata bearing parallel lines ranging from light to dark brown. A further observation from Réunion Island in the Indian Ocean ( Bachel 2010) was also considered to be C. incola by Rudman (2010) bearing the same parallel lines along the cerata but lacking in the yellow-orange band of the earlier observation. All animals appear to have dark brown-grey rhinophores and the same dark colour anterior to the pericardium. Specimens from Koh Tao have been observed to show external variability (Fig. 17F, G ) and further investigation is required.

Figures

Figure 17. A, B Aeolidiopsis ransoni 23 mm (A) and 25 mm (B) C Baeolidia salaamica 10 mm D Cerberilla ambonensis 20 mm E Cerberilla asamusiensis 8 mm (photograph by Pau Urgell Plaza) F, G Cerberilla cf. incola variants 12 mm (F) and 7 mm (G) H Cerberilla sp. 22 mm I Limenandra confusa 12 mm J Caloria indica 26 mm K Favorinus sp. 1 5 mm L Favorinus sp. 2 5 mm