Two new sacoglossans (Gastropoda: Opisthobranchia) from Thailand

Two new sacoglossans were found in brackish mangrove habitats near Pattani in the southern part of the Gulf of Thailand. Both are small species (< 10 mm) living hidden in clay with small green algae high in the intertidal zone becoming not submerged for days. They have black pigment on the dorsal side and their bodies clearly consist of two parts. One is named Gascoignella nukuli n. sp., which looks similar to G. aprica Jensen, 1985 from Hong Kong, but differs in radula, penial spine, body proportions and habitat. The other is G. jabae n. sp., which has two parallel cerata instead of a visceral sack on the posterior side of the body.