Pulmonata

Pulmonata or pulmonates is an informal group (previously an order, and before that, a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includes many land and freshwater families, and several marine families. The taxon Pulmonata as traditionally defined was found to be polyphyletic in a molecular study per Jörger et al., dating from 2010. Pulmonata are known from the Carboniferous period to the present. Pulmonates have a single atrium and kidney, and a concentrated symmetrical nervous system. The mantle cavity is on the right side of the body, and lacks gills, instead being converted into a vascularised lung. Most species have a shell, but no operculum, although the group does also include several shell-less slugs. Pulmonates are hermaphroditic, and some groups possess love darts.