We have seen more than 50 Gymnodoris striata in the Marshalls, all from Enewetak Atoll. So far we have not seen it at Kwajalein despite extensive searching, although Stan Jazwinski photographed one at Ailinglaplap Atoll. At Enewetak, they could often be found in groups exposed on sand or sand and rubble bottoms at depths of about 5 to 15 meters. They are relatively large, up to about 50mm in the photos below. They can easily be recognized by the orange margin and orange dorsal ridges, and by the peculiar gills, which form longitudinal plates. It was these gills that prompted Risbec (1928) to erect a new genus, Analogium, for them. The general consensus nowadays seems to be to leave them in Gymnodoris until a more general anatomical comparison can be made with other members of the family. Gymnodoris striata was first reported in the Marshalls from Enewetak Atoll by Johnson & Boucher (1984).
Stan Jazwinski's Ailinglaplap specimen is immediately below. It was on sand at night in 9-10m on the lagoonside of Beran Island.
Below shows a pair mating. It also provides a good view of the plate-like gills. I don't know what's up with the facial expression (?) of the individual on the right.
This animal is depositing an egg mass in captivity on the side of a fiberglass sea table.
Gymnodoris striata seems to exclusively eat members of the sacoglossan genus Plakobranchus, as shown in the photos below.
Created 1 January 2007
Updated 3 August 2021