Blue nudibranch in coral reef

Lettuce Sea Slug (Elysia crispata) is Found in algal beds to shallow reef areas of up to 15 meters (50 feet) deep, you can easily identify this sea slug due to the lettuce-like appearance of its upper mantle. This is one of the nudibranch species that shows poecilogonomy which a conditional larval development triggered by environmental cues.