Flabellina rubrolineata

Seen in Malapascua, Philippines (2012). Photo by Mark Bockstael, my husband.
It is a species of sea slug, an aolid nudibranch, in the family Flabellinidae. It can grow to 3 cm and its color can variate from cream or pink to violet, rhinophores with darker tone in their tips.
Habitat: This species is distributed in the Western Pacific Ocean and can be commonly found in the Philippines and Malaysia.