Oxychiloidea

Oxychiloidea is a taxonomic superfamily of terrestrial pulmonate gastropods within the clade Stylommatophora. In traditional classifications it was used to group several lineages of small to medium-sized glassy-shelled snails, but its exact composition has varied across authors and over time. In modern systems, the membership of Oxychiloidea is not consistently defined, and some families previously placed here have been reassigned as classifications are revised through molecular data.

The best-known member is the family Oxychilidae, commonly referred to as glass snails. Other families have historically been included in Oxychiloidea in different schemes, such as Daudebardiidae, but the precise list of constituents differs among taxonomic treatments and has shifted with new evidence.

Morphology and ecology of the group are broadly characterized by thin, translucent shells and a small to medium body size. Members are terrestrial pulmonate snails that prefer moist habitats, including leaf litter, under bark, and damp soil. Their diets are mainly detritivorous and fungivorous, feeding on decaying plant material and microfungi.

Distribution and habitat range from the Palearctic region to parts of Asia, with European and other temperate-zone taxa being particularly prominent. Some species have been introduced beyond their native ranges. The fossil record for Oxychiloidea is relatively sparse, while molecular studies continue to refine the relationships within Stylommatophora and the exact placement of Oxychiloidea relative to related groups.