About Felimare orsinii (Vérany, 1846)
Felimare orsinii is a member of a group of very similar Felimare species native to the Mediterranean Sea. This species can be told apart from other similar species by its entirely blue gills and rhinophores, and small raised tubercles on its back. It has a single median white line with a faint blue edge, and a white line along the edge of its mantle that fades to yellow on the sides of its body. The maximum body length of this species is 20 millimeters. Felimare orsinii feeds on the sponge Scalarispongia scalaris. This species was previously known as Hypselodoris orsinii; in 2012, all Atlantic species of Hypselodoris were found to belong to a separate clade, and were moved to the genus Felimare. This nudibranch occurs in the Western Mediterranean Sea. Specimens from the Eastern Mediterranean do not have yellow color in their submarginal line, but are still classified as the same species.
