Opisthobranch of the Week Data
Dendrodoris albopurpura is very similar to D. elongata, but the presence of conical warts all over the dorsal surface of D. albopurpura (none in D. elongata) would seem to separate the two species externally. Bill Rudman (1999) points out in the Slug Forum that there is considerable confusion in the literature concerning these two species, and that there are earlier names for both animals.
Dendrodoris albopurpura is considered to be very rare on Okinawa as I have seen and collected only a single individual as of early 2001. The above featured, but uncollected, animal is one which was photographed in the waters of Yakabi Island, one of a series of islands in the Kerama Islands Group, which are located 30 ~ 40 kilometers west of the Okinawa capitol, Naha. There are four main islands in the Kerama Islands: Tokashiki, Zamami, Aka, and Geruma Islands, as well as many small uninhabited islands. This featured animal was photographed by Atsushi Ono (1999) in mid-1998 and is used here with his kind permission. This same animal is featured in his Opisthobranchs of Kerama Islands, 1999, photo # 221, p. 133.
The solitary Okinawa-collected animal was found in 55m beneath a large slab of coral rubble as it was being overturned. Later at home the specimen was noted to exuded copious amounts of a transparent mucus as it was placed into the relaxant (propylene phenoxytol) prior to fixation in formalin. I asked to use Atsushi's photograph here as the only two images of the Okinawa-collected specimen are so badly under-exposed as to be unusable.
There are eight described species of Dendrodoris known from Okinawan waters as of late-December, 2003). These eight species are:
D. albopurpura (the above featured animal) D. carbunculosa D. coronata D. denisoni D. elongata D. fumata D. nigra D. tuberculosa