superorder of molluscs

The Heterobranchs are a large group of snails and slugs. The group includes marine, aquatic and terrestrial gastropod molluscs.

Four examples of Heterobranchia
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Heterobranchia
J.E. Gray, 1840
Taxonomic subcategories

informal group Lower Heterobranchia
clade Nudipleura
clade Euopisthobranchia
clade Panpulmonata

Heterobranchia is one of the main clades of gastropods. It has three informal groups: [1] The details are extremely complicated, and not yet quite worked out. Experts say they have "poorly resolved phylogenetic relationships".[2]

  • Lower Heterobranchia: a group of rather specialized, highly evolved sea slugs and sea snails.
  • Opisthobranchia: almost all are marine species, some shelled and some not. They are a group of slugs and snails with grinding gizzard plates.
  • Pulmonata. This is a group which is familiar to most people. It includes most land snails and slugs, many freshwater snails and a few marine species. They breathe air, are hermaphrodite, and usually have no operculum.[3]


  1. Bouchet P. & Rocroi J.-P. (eds) 2005. Classification and nomenclator of gastropod families. Malacologia: International Journal of Malacology. 47(1-2). [1]
  2. Dinapoli A. & Klussmann-Kolb A. 2010. The long way to diversity – phylogeny and evolution of the Heterobranchia (Mollusca: Gastropoda). Molecular Phylogenetics and Evolution 55 (1): 60–76. [2]
  3. The operculum is the hard section on the foot which closes up the shell so the animal is safe inside.