Opisthobranch of the Week Data
Melibe pilosa is considered to be very rare on Okinawa as I have seen and collected only two animals over a period of a good many years of diving here. Gosliner (1987) reports that the animals are commonly found in the Hawaiian Islands, where they inhabit intertidal and shallow subtidal reef and sand flats. The featured animal was discovered on the surface of a large patch of open sand in relatively deep water (61m); it was "flattened" in the sand and on initial inspection it appeared to be a polyclad flatworm. Upon picking it up, it was obviously not anything closely resembling a flatworm.
As of this writing (June, 1999) I've found only two confirmed Melibe species on Okinawa: M. fimbriata and M. pilosa; there is also a possibility that I have M. mirifica here as well, but the specimen identification has not yet been confirmed. In addition to the preceding three animals, I've also found a very small undescribed species which is sometimes collected in large numbers from 4.6m or less.
Melibe species are well known to feed upon microcrustaceans, which are trapped within the large distendable oral hood (the oral hood is apparent in the above featured animal).