Like Elysia sp. e116, this unidentified Elysia is usually found on the algae Tydemania. During the day it hides down in the clump of algae and is hard to find. At night, they are often out on the surface of the algae clump. This animal is figured on the Sea Slug Forum as Elysia sp. 2 and in Gosliner et al (2018) as Elysia sp. 21. The first photo is from Enewetak Atoll.
The next three photos show an 8mm specimen found crawling on algae at a depth of about 30m on the Kwajalein Atoll seaward reef on 16 February 2010.
The specimen below was on Tydemania algae on a southern atoll lagoon pinnacle.
Created 20 February 2009
Updated 18 February 2021