Stylommatophora is an order of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This taxon includes most land snails and slugs. Stylommatophorans lack an operculum, but some close their shell apertures with temporary "operculum" (epiphragm) made of calcified mucus. They have two pairs of retractile tentacles, the upper pair of which bears eyes on the tentacle tips. All stylommatophorans are hermaphrodites.
Helicinidae is a family of small tropical land snails which have an operculum. They are terrestrial operculate gastropod mollusks in the superfamily Helicinoidea.
Planorbidae, common name the ramshorn snails or ram's horn snails, is a family of air-breathing freshwater snails, aquatic pulmonate gastropod molluscs. Unlike most molluscs, the blood of ram's horn snails contains iron-based hemoglobin instead of copper-based hemocyanin. As a result, planorbids are able to breathe oxygen more efficiently than other molluscs. The presence of hemoglobin gives the body a reddish colour. This is especially apparent in albino animals.
Zonitidae, common name the true glass snails, are a family of mostly rather small, air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Zonitoidea.
Retinella is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Gastrodontidae.
Vitrea is a genus of small, air-breathing land snails, terrestrial pulmonate gastropod molluscs in the family Pristilomatidae.
Zonitoides is a genus of air-breathing land snails, terrestrial gastropod mollusks in the family Gastrodontidae.
Hygromiidae is a taxonomic family of small to medium-sized air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea.
Sphincterochilidae is a taxonomic family of medium-sized air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea.
Elonidae is a family of air-breathing land snails, terrestrial pulmonate gastropods mollusks in the superfamily Helicoidea.
Vitrinidae is a family of small, air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Limacoidea.
Trochomorphidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Gastrodontoidea. Since 2017, its classification has been revised and it now belongs to the superfamily Trochomorphoidea
Aegopinella is a genus of small, air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Gastrodontidae, the glass snails.
Punctum is a genus of very small air-breathing land snails, terrestrial pulmonate gastropod mollusks or micromollusks in the subfamily Punctinae of the family Punctidae, the dot snails.
Perpolita is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Gastrodontidae.
Janulus is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Gastrodontidae.
Mesomphix is a genus of terrestrial gastropods belonging to the family Gastrodontidae.
