Hypselodoris maculosa (Pease, 1871)

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 : 36

Hypselodoris maculosa (Pease, 1871) Plate 50

Hypselodoris maculosa . - Rudman 1986: 340, figs. 1, 13, 16-18 (Red Sea, Tanzania, Christmas Island + W Pacific); Yonow 1989: 302, pl. 21 (Red Sea); Yonow et al. 2002: 858, fig. 13e (Chagos); Apte 2009: 170, fig. 2i (Laccadive Islands).

Material.

Seychelles: 15 × 5 mm (PK-DD), Lilôt, NW Mahé, 17 m depth on granite wall, 26 April 1992, leg. P Kemp. - Maldives: 15 mm length, Maayafushi, Ari Atoll, 3m depth, on coral rubble encrusted with algae and sponges, March 1997, leg. J Hinterkircher. - La Réunion, Mauritius, and Mayotte: numerous photographs http://seaslugs.free.fr/nudibranche/a_intro.htm. - Sri Lanka: photographs of one individual, Unawatuna, S of Galle, 27 December 2010, S Kahlbrock.

Description.

Elongated body with spatulate head. Translucent body with opaque white markings comprising several longitudinal white lines on dorsum and small white dots on orange-red margin. Magenta spots and patches between dorsal white lines. Foot translucent with magenta spots and patches, and small white dots. Rhinophores distinctive with white core bearing two red bands. Gills small, held upright, red proximally and white distally.

Remarks.

Small specimens are similar to several species of Thorunna , such as Thorunna australis (Risbec), recorded only from South Africa in the western Indian Ocean: it also has orange bands on the gills and rhinophores but the white markings are limited to one or two lines on the dorsum. Thorunna florens (Baba) also has similar gills and rhinophores but has purple spots around the margin as well as an orange border to the frontal margin, and it is limited to the western Pacific. Several un-named species are illustrated in Gosliner et al. (2008) but at present they are only known from few localities in the western Pacific.