Ercolania coerulea

Ercolania coerulea is a species of small sacoglossan sea slugs, shell-less marine opisthobranch gastropod mollusks in the family Limapontiidae.

Description

It has a cream body with extensive green branches of the digestive gland and scattered white flecks. The cerata are greatly inflated and decorated with iridescent blue-white flecks. Occasionally, there are a few brown flecks on their dorsal surfaces. There are carrot-shaped branches of the digestive gland in the centers of the cerata and thin, lateral branches in the tips of the central ones. The pericardium is opaque white.

Distibution

In the Indo-Pacific.

Habitat

It is found in moderately protected to moderately exposed rocky habitats at depths of about 1 m. It usually occurs in association with green algae of the genus Dictyosphaeria which it feeds on (mostly Dictyosphaeria cavernosa). It shows a preference for resting on its host alga while held and is superbly camouflaged on it. When resting, it contracts slightly so its cerata create a circular outline resembling a small lobe of the alga and the individual cerata closely resemble the algal cells. It readily autotomizes the central cerata when disturbed and lays a flattened white egg mass.