Pleurobranchus forskalii

Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: Pleurobranchida
Family: Pleurobranchidae
Genus: Pleurobranchus
Species: Pleurobranchus forskalii

Pleurobranchus forskalii is a side-gill slug in the family Pleurobranchidae. Side-gill slugs are not true nudibranchs: their gill sits along the right side of the body under the mantle.

It is a large, soft-bodied slug, red to reddish brown, with a pattern of pale lines forming a net over the back. The book describes animals the size of dinner plates.

Side-gill slugs are mainly active at night, and many can release acidic secretions as a defence.

The book notes that most side-gill slugs are hard to find in the Philippines, but this one is the exception and comes out at night on many sites. On one night dive in Dauin, a dozen or so glowing red animals were spread across a seagrass field. Bring a good torch and give them plenty of room.

The book spells the name "foskalii"; the accepted spelling is forskalii.

It appears on page 21 of Nudibranchs of the Philippines.

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