The Pleurobranchidae are a taxonomic family of sea slugs, marine gastropod molluscs in the clade Pleurobranchomorpha.

Characteristics

Species in the family Pleurobranchidae have a prominent mantle and an internal shell that becomes reduced or is lost completely in adults. Some adult species have been seen feeding on ascidians. Larval pleurobranchids can be planktotrophic (feeding on plankton), lecithotrophic (deriving nutrition from yolk), or direct developing. Like all Pleurobranchomorpha, they breathe through an external gill, located on the right side (contrary to nudibranchs who have it on the back), just after the genital organ. Many species produce secretions from their rich glandular mantle as a chemical defense against predators. Even the production of sulfuric acid has been reported.

Taxonomy

Until 2005, this family was placed in the suborder Notaspidea. However, in the taxonomy of Bouchet & Rocroi (2005), the family Pleurobranchidae was placed in the superfamily Pleurobranchoidea, the only family belonging to the subclade Pleurobranchomorpha (sister to the subclade Nudibranchia), part of the clade Nudipleura.

Subfamily Pleurobranchinae