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Platydoris sanguinea Bergh, 1905
(fig. 12, pl 6 figs 2, 3)
Platydoris sanguinea Bergh, 1905: 139, pl. 2 fig. 9, pl. 16 figs 4, 5; Dorgan et al., 2002: 293, figs 2n, 20b, 24-26.
Platydoris sp. 2 Marshall & Willan, 1999: 82, fig. 145.
Material.— RMNH.MOL.131653, RBE Stn 21, Mamala, Hitu, 10 m depth, 21.xi.1990, leg. A. Fortuin, 17 × 6 mm pres., photos M. Lavaleye 26-19/20.
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Fig. 12. Platydoris sanguinea. View of head and oral tentacles of 75 mm specimen.Platydoris formosa Eliot, 1903: 376; Eliot, 1906a: 646 [non P. formosa (Alder & Hancock, 1864)]. |
Description.— The body is oval with an irregular wavy edge (pl. 6 fig. 2), very flat with a prominent visceral hump extending from behind the rhinophores to the gills. The opaque colour was deep orange-red with pale areas where the pigment was less dense or even absent. There were two paired patches of white or grey speckling on the edge of the visceral hump, the same speckled colouration on the gills, rhinophores, and edge of the mantle. The rhinophores had a red stalk and the clavus was deep red with white speckles, the speckling increasing towards the tip; there are 19 lamellae on the clavus. The six tripinnate gills were speckled and the anal papilla was red.
The preserved specimen is relaxed but very stiff, and the speckled gills and the rhinophores are well extended. The margins of the rhinophore openings are scalloped, and there are six distinct lobes around the gills. The sand-like markings are no longer visible on the dorsum, which is finely granulated. Ventrally the hyponotum is beige brown. The foot sole is neither orange nor yellow, but was certainly coloured in life; there is a dense brown line along the edges of both the upper and the lower surfaces of the opaque creamy foot (pl. 6 fig. 3). The head is bilaminate with a divided upper lamina, and the oral tentacles are long and digitiform (fig. 12).
Remarks.— This species appears to be rarely recorded, and only one specimen is present in this thorough collection; it has been previously recorded from Indonesia and the Philippines (Bergh, 1905; Dorgan et al., 2002), but there are also records from East Africa, southern India, and Sri Lanka (Eliot, 1903, 1906a as P. formosa) which were omitted from the review (Dorgan et al., 2002). These considerably extend the range westwards to the western Indian Ocean, although it has not been recorded in the Red Sea (Yonow, 2008). Marshall & Willan (1999) described and illustrated this species from the Great Barrier Reef and they also observed that the dorsum looks as if sand has been scattered on it. The accretions lacking in the preserved material may not be problematic, as Eliot stated that they were lacking in his smaller preserved specimens (Eliot, 1906a: 646); this Ambonese specimen was only 17 mm in preservative while the species grows to 45 mm.