Opisthobranch of the Week Data
Dendrodoris denisoni is considered to be uncommon on Okinawa; I've collected seven animals, but perhaps a score or so of others have been seen but neither photographed nor collected. Unlike most species of Dendrodoris which have a smooth notum, D. denisoni has prominent tubercles on its back, nevertheless it's quite smooth to the touch. The brown mottled notum in conjunction with the small bright blue spots distinguishes this attractive dorid from any others found on Okinawa.
The above featured animal was found crawling amid a live stony coral reef from beneath dense growths of mixed Acropora and Porites corals. There were dense colonies of feather hydroids and encrusting bryozoans in the immediate vicinity of the collected animal. It's perhaps interesting to note that the majority of these attractive dorids seen on Okinawa are found crawling on the surface of fine sand near spur and groove formations of live coral reef environments.