Opisthobranch of the Week Data
Phidiana bourailli is considered to be rare on Okinawa as I have seen and collected a total of five individuals. The above featured animal was collected from a mixed live/dead stony coral reef amid spur & groove formations during a late morning SCUBA excursion. Specifically, it was collected from a small tuff of an unknown brown filamentous alga.
Marshall & Willan (1999) point out similarities between P. bourailli and several other aeolids. The following is taken from their publication:
P. bourailli is also similar to Cratena lineata and C. simba in possessing white streaked cerata . . . . However the resemblance between P. bourailli and these two species of Cratena are more than superficial, possibly indicating the generic placement of P. bourailli needs reassessing - it could be a species of Cratena.The C. lineata and C. simba mentioned above are currently unknown from the main island of Okinawa at this time (early-December, 2001), however, both C. lineata and C. simba are found in the nearby Kerama Islands Group, located 30 ~ 40 kilometers west of the Okinawa capitol, Naha.