While not abundant, Platydoris scabra is probably the least uncommon large cryptobranch dorid in Marshalls. We have seen specimens at Kwajalein, Enewetak, and Utirik Atolls, and there are additional records below from Majuro and Wotje. They are typically found under dead coral on lagoon reefs at depths of 1 to 8 meters. The harbor on Kwajalein has been one of the best places to find them, where they often live under sheets of aluminum siding blown into the water during storms. Larger specimens often exceed 100mm in length. Platydoris scabra was listed without description in the Marshalls from Bikini Atoll by Marcus (1965).
The two photos below show Platydoris scabra with its egg masses.
We originally listed the small, 7mm long yellow one with black spots in the first five photos below as a separate unidentified species, but a nice series of photos of different sized individuals from Majuro and Wotje provided by John and Lynette Flynn (FreeDivePhoto) plus one of ours from Utirik shows pretty conclusively that they are all growth stages of Platydoris scabra. The first three below is one individual from a depth of 8m on a Kwajalein lagoon pinnacle.
The next two are from Christina Sylvester from about 2m on the lagoon side of Kwajalein Island.
The 17mm Majuro specimen from John and Lynette Flynn clearly bridges the gap between the juveniles above and more obvious specimens of P. scabra.
The Flynn's 27mm specimen is definitely a young P. scabra with a diminishing yellow margin. Note the similarity in the gills with the other specimens.
Our 30mm Utirik specimen still has the yellow margin and has retained a bit of yellow around the gill and rhinphore pockets.
A 35mm Majuro specimen has a fading yellow margin.
At 60mm, this Majuro specimen has typical adult coloration.
John and Lynette Flynn also found a giant 120mm individual at Wotje Atoll.
Created 15 December 2006
Updated 4 November 2021