Chelidonura hirundinina (Quoy & Gaimard, 1833)

Yonow, Nathalie, 2012, Opisthobranchs from the western Indian Ocean, with descriptions of two new species and ten new records (Mollusca, Gastropoda), ZooKeys 197, pp. 1-130 : 4-5

Chelidonura hirundinina (Quoy & Gaimard, 1833) Plate 3

Bulla hirundinina Quoy & Gaimard, 1833: 367, pl. 26, figs. 20-25 (Mauritius).

Chelidonura philinopsis Eliot, 1903a: 336 (Zanzibar); Rudman 1973b: 203, figs. 1, 2, 3D, 5 (Zanzibar).

Chelidonura hirundinina . - Macnae 1962: 194 (South Africa); Gosliner 1987: 42, fig. 11 (South Africa); Gosliner 1988: 90, fig. 9 (Aldabra, Seychelles).

Material.

Maldives: three specimens, approx. 5-6 mm length pres., Kuredu, Lhaviyani Atoll, on sandy substrate in shallow water, 10-24 March 1998, leg. J Hinterkircher; several individuals, photos only, 1986-1994, J Hinterkircher. - La Réunion: photographs of numerous individuals, 10 - 40 mm http://seaslugs.free.fr/nudibranche/a_intro.htm.

Description/Distribution.

Dark brown to black body with black and orange edging, vivid blue Y- or T-shaped mark on head, small white patch at posterior end of head shield, and large white crescent-shaped mark on posterior shield. The species is rarely recorded in the Indian Ocean, where the pattern is relatively consistent, and somewhat different to those from the Pacific Ocean. Gosliner (1988) comments on the different colour forms, and that two colour forms were recorded mating in South Africa. Chelidonura hirundinina is recorded in the Mauritius - La Réunion region, the type locality, and it has a circumtropical distribution (also found in the Caribbean, Thompson 1977). Most records are from the western Pacific, where it is larger, more abundant, and more variable in colour and pattern, although the variations exhibited by http://seaslugs.free.fr/nudibranche/a_intro.htm are substantial.