Trigonochlamydidae is a family of air-breathing land slugs, terrestrial gastropod molluscs in the clade Eupulmonata (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

The native distribution of Trigonochlamydidae includes Caucasus,[1] Iran and Turkey.

[3] Previously, Trigonochlamydidae was placed in the superfamily Trigonochlamydoidea Hesse, 1882, in the subinfraorder Sigmurethra.

The following two subfamilies have been recognized in the taxonomy of Bouchet & Rocroi (2005): There are nine[3] genera in the family Trigonochlamydidae with a total of 11 species: Subfamily Trigonochlamydinae Subfamily Parmacellillinae Synonym: Selenochlamys O. Boettger, 1883 has been removed from the Trigonochlamydidae to the Oxychilidae based on DNA evidence.

[8] The following cladogram shows the phylogenic relationships of this family with the other families in the limacoid clade:[9] Staffordiidae Dyakiidae Pristilomatidae Chronidae Euconulidae Trochomorphidae Gastrodontidae Oxychilidae Trigonochlamydidae Parmacellidae Milacidae Zonitidae Helicarionidae Ariophantidae Urocyclidae Vitrinidae Boettgerillidae Limacidae Agriolimacidae