Aliculastrum debilis (Pease, 1860)

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

Aliculastrum debilis (Pease, 1860) Figure 6F, G

Material examined.

Two specimens 30 mm, LB; one specimen 28 mm, TB.

Ecology.

Extremely similar to A. cylindricum (see above). Often found together with other Haminoeidae species from Koh Tao, apart from Atys sp. As part of the present surveys, observations were made of hunting and capture of specimens of A. debilis by the stomatopod Haptosquilla cf. nefanda (Fig. 6G ). Captured animals were taken into burrows made by the crustacean. While active feeding was not observed, it should be noted that shells of A. debilis , A. cylindricum , and rarely Atys semistriatus Pease, 1860 can be found in high abundance around the holes of H. cf. nefanda and other mantis shrimps in the soft sediment habitats. These shells are often broken, but not always, and are likely indications of predation by these crustaceans, which are abundant in these habitats. Depth 8-18 m.

Distribution.

Across the western Pacific including the Philippines, Guam, Tahiti, Fiji, and Hawaii ( Too et al. 2014). Known from the Gulf waters of Thailand ( Mehrotra and Scott 2016).

Figures

Figure 6. A Elysia pusilla 7 mm B Elysia cf. tomentosa 37 mm C Thuridilla cf. gracilis 18 mm D Colinatys sp. 3 mm E Aliculastrum cylindricum 30 mm F Aliculastrum debilis 28 mm G A. debilis (shell 12 mm) captured alive and predated by Haptosquilla cf. nefanda H Roxaniella multistriata 9 mm I Atys semistriatus 8 mm J Atys sp. 11 mm K Diniatys dentifer 5 mm L Diniatys dubius 6 mm.