Limoniidae is the largest of four crane fly families, with more than 10,700 species in more than 150 genera. Some studies have suggested it to be a paraphyletic group, with some limoniids being more closely related to Tipulidae and Cylindrotomidae than to other limoniids. Limoniid crane flies can usually be distinguished by the way the wings are held at rest. Limoniids usually hold/fold the wings along the back of the body, whereas other crane flies usually hold them out at right angles. Snow flies (genus: Chionea) such as Chionea scita have no wings at all. Limoniids are also usually smaller than other crane flies, with some exceptions.

The classification of Limoniid crane flies has been varied in the past, with the group treated both as subfamily and family, but the following classification is currently accepted. (Species counts are approximate, and vary over time.). Recent phylogenetic analyses have revealed the family to be paraphyletic and further research is suggested.

Family Limoniidae (Limoniid Crane Flies, more than 10,700 species)

Subfamily Chioneinae (4,324 species and subspecies)

Subfamily Dactylolabinae (59 species and subspecies)

Subfamily Limnophilinae (2,593 species and subspecies)

Subfamily Limoniinae (3,873 species and subspecies)

Subfamily †Architipulinae (extinct)

Subfamily †Drinosinae (extinct)

Subfamily †Eotipulinae (extinct)

These flies are found in damp places throughout the world, and many species form dense swarms in suitable habitats.

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