Photo courtesy of David Cowdery
Goniobranchus sp. 20 (Undescribed)
Johnson & Gosliner (2012) rearranged many taxa in the family Chromodorididae. Specially they split the genus Chromodoris in two and resurrected Goniobranchus Pease, 1866, for some members. Goniobranchus differs from Chromodoris having different kinds of glands along the edge of the mantle which secrete noxious chemicals they metabolize from the sponges they feed on, when disturbed.
Members of Goniobranchus also lay egg coils that are upright attached to the substrate along one edge of the ribbon, whereas in Chromdoris the egg coil is laid flat to the surface. Some species raise and lower their heads and mantles as they crawl. This mantle flapping behavior is thought to increase the amount of oxygen the critter can capture from the seawater.
Goniobranchus sp. 20 is one of 46 undescribed species belonging to this genus that we are aware of. See Nudibranch and Sea Slug Identification . Its coloration is complex with brown pigment on the white notum, with a sprinkling of opaque white specks. It has a series of yellow spots along the ruffled notal margin. The gill and rhinophores are grey with white specks.
Thanks again for sharing David.
Dave Cowdery is a retired biomedical engineer and Divemaster at Byron Bay Australia. He has over 5000 logged dives. He is a keen participant in trips organized by Graham Abbott at Diving4Images and has dived the tropics extensively from Cocos Keeling Islands east to Niue. 3 Camera equipment used: D800 with DS160 substrobes
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