Haminoea virescens

Dear Jessica,
Offhand I don't know of any studies on the biology of Haminoea virescens. If anyone else does could that let us know please. I have posted a picture of a tropical species, Haminoea cymbalum which is a most unusual member of the genus in being brightly coloured.

I am puzzled by Abbott's note that H. virescens is a species of the open coast, because most species of the genus live in sheltered bays and estuaries on sand flats or sandy-mud. I know of a couple of interesting studies on species of Haminoea which should be available to you.

One of these describes the ability of the European species, Haminoea navicula, to change colour to match its surroundings. The colour pigments in its skin are contained in ramifying epithelial and subepithelial cells. By the extension and contraction of parts of these "melanophores" colour pigments can be moved or obscured so that the skin colour can change from black or dark brown to white in four or five hours. (Edlinger,1982).
It is probable at least some of the many other species which are mottled in patches of browns, greys and blacks also have the ability to change colour.

The other describes the relationship between growth and reproduction in Haminoea japonica and the seasonal occurrence of its algal food.

References:
Edlinger,K., 1982. Colour adaption in Haminoea navicula (da Costa) (Mollusca: Opisthobranchia). Malacologia, 22: 593-600.

Ito,K., Goshima,S. & Nakao,S. 1996. Growth and reproduction of the generalist opisthobranch Haloa japonica: effect of algal seasonality on growth rate. Marine Biology, 126: 395-401.