OKINAWAN
OPISTHOBRANCH OF THE WEEK

Opisthobranch of the Week Data

Taxonomy:

        Chromodoris willani is considered to be common on Okinawa, although I have collected only eleven specimens since May, 1984, many others have been seen and photographed. This is the most commonly observed deep water opisthobranch found here; I frequently see a half dozen or so during deep water excursions. These attractive animals are usually a distinctive blue color, but occasionally they are found as a silver form. The only other chromodorid found here in the Ryukyus Archipelago which is closely similar in appearance is Chromodoris lochi, but the distinctive tiny white opaque spots on both the gills and rhinophores of C. willani clearly distinguish the two from each other.

        Chromodoris willani is commonly found between 130ft and 200ft (40 ~ 61m), usually amid coral rubble where it apparently feeds upon sponges.