Family Diplopeltidae Filipjev, 1918

Diagnosis. (Modified from Fonseca & Bezerra (2014).) Cuticle smooth, striated, or annulated. Labial sensilla papilliform or indistinct, four cephalic setae present. Amphideal fovea loop-shaped, cryptospiral, or cryptocircular (i.e., with similar outline as cryptospiral but without a central spot). Ocelli present or absent. Buccal cavity funnelshaped, cup-shaped, cylindrical, or minute; teeth absent. Pharynx with or without posterior bulb; pharyngeal tubes usually visible. Female reproductive system usually with two outstretched ovaries. Male reproductive system usually with two testes; when present, posterior testis is either anteriorly oriented and reflexed or posteriorly directed and outstretched. Precloacal supplements usually absent. Tail conical or conico-cylindrical. Caudal glands have joint or separate outlets.

Remarks. Pictorial and tabular keys to the genera of Diplopeltidae were provided by Tchesunov & Miljutina (2008).