Sky Blue Phyllidia

Phyllidia coelestis is a species of sea slug, a sacoglossan, a shell-less marine gastropod mollusc in the family Phyllidiidae. Description This sea slug is up to 6 cm in length. The body is elongated and slug-shaped. The mantle has a grey-blue background color; the margin is covered with many small tubercles. Bigger tu... Read more in Seabook