Description below Side=gilled Sea Slugs
The polygon shaped pattern on these side-gilled slugs, and their striking rose/pink/magenta and sometimes gold colouring makes them a treat to find. The three individuals documented here were between 2 and 3″ (50 mm to 75mm) and found in lagoons or fishponds in the North Kihei and Makena area of Maui. They are nocturnal animals who hide in rock crevices and under boulders during the day. My first sighting came as a result of a wicked wave in about 2 ft of water which exposed the side of a sand and algae-covered rock. The bouncing rhinophores and brilliant markings made it stand out from the surrounding sponges and coraline algae. They have a rather complicated taxonomic history which is laid out in detail on the Sea Slugs of Hawaii website. They are sometimes mistaken for the Pleurobranchus varians, but the tubercles are much more pronounced and they lack the white bumps.