Opisthobranch of the Week Data
Aldisa sp. 3 is considered to be very rare in the waters of Okinawa's main island as I have seen and collected only the above featured animal. The animal was found on the surface of one of many concrete pilings supporting the Tengan Pier; the piling were covered with numerous encrusting organisms (bryozoans, poriferans), bivalves, cnidarians and others. As with other species of Aldisa, Aldisa sp. 3 probably feeds on sponges. Ova were not found associated with the specimen. I've also added an additional page showing the foot view of the same animal.
Aldisa sp. 3 is a moderately-sized dorid nudibranch having gills which can be retracted into a pocket within the mantle. The body feels relatively firm due to imbedded spicules within the skin. The mantle is much wider than the foot and has a series of small raised dorsal pustules having black centers which are uniform in size.
I've earlier featured two described species of Aldisia found found in Okinawan waters, Aldisa albatrossae and Aldisa pikokai, as well as three additional unknown animals, Aldisa sp. 1, Aldisa sp. 2, and Aldisa sp. 4.