Opisthobranch of the Week Data
Chromodoris aureopurpurea is indeed a beautiful nudibranch and considered to be rare on Okinawa; I've seen and collected a total of five individuals, with the initial specimen being collected in early August of 1991. The above featured animal was found crawling on the surface of mixed silty-sand and strewn oyster shell rubble beneath the concrete pier pilings of Tengan Pier.
There are two similar appearing species of Okinawan chromodorids, Chromodoris alius, and C. rufomaculata, however these two can be separated from C. aureopurpurea by noting the position of the submarginal spots of C. aureopurpurea; in the other two species the spots are at the margin of the mantle.
The species was originally described from China by Collingwood in 1881. It's interesting to note that Rudman (1987) points out the two Japanese specimens he examined from Sagami Bay are identical in color to Collingwood's original description but lack the yellow mark on the inside edge of each purple color spot which is seen in the Australian material. The Okinawan animals are similar to those seen in mainland Japan waters.