Hawaiian Yellow-tip Sea Cucumber (Stichopus sp. 2) size 20cm
The Hawaiian Yellow-tip Sea Cucumber is rare and only known from Hawaii. It still has not got a proper scientific name. This is the only one that I remember seeing. It was under a rock in the day so, they may be nocturnal or just stay under rocks. Kauai 2017
A closer look at the Hawaiian Yellow-tip Sea Cucumber. Kauai 2017