Trinchesia alpha (Baba & Hamatani, 1963)

コヅチミノウミウシ Trinchesia alpha
Photographed by
bighit2000 Manabu Kakegawa
Wannai, Osezaki, Higashiizu, Japan
Water temperature


Matured, length 13mm (Code Ac of Rrsso-DoMINGUEZ, 1963). Head broad as shown in Cuthona nana. Simple rhinophores. Rounded foot-corners. Branchial papillae long fusiform, and arranged in 9 simple oblique rows on each side. Genital orifices between and below the 1st and 2nd rows on the right side, the anus in front of the inner corner of the post-anal row, the nephroproct preanal. General body-colour translucent yellowish white covered thickly with opaque white dots on the head region in the middle line, on the cephalic tentacles and rhinophores, and on nearly the whole length of the branchial papillae, on their outer surface. Both the cephalic tentacles and rhinophores tinged with vivid orange. Liver-diverticula within the branchial papillae yellowish brown. Liver branching as usual in Cuthona (and Catriona), the right liver and the left-sided partner containing 4 simple canals. Blind-sac of stomach not determined. Simple salivary glands. Oral glands as in Catriona. Simply elongated kidney. Jaw-edge (?). Radula colourless, the formula about 80 X 0.1.0. Median cusp of the teeth retracted (Catriona type), lateral denticles 2-3 one each side, these latters often seen interspersed by smaller ones among them. Penis elongated conical, muscular, and not armed with a stylet (Cuthona type). A penis gland attached to the base of the penis. About 7 testes, each accompanied by several ovaries.