33 species of which 31 (93.9%) are endemic -
2 genera of which none are endemic
(as of December 31st, 2018).
The two genera of this family were previously included in
Boidae (e.g., Dowling 1959; Stimson 1969; Goin, Goin & Zug 1978).
Now recognized as a separate family (e.g., Smith, Smith & Sawin 1977; Zug, Vitt & Caldwell 2001).
Ungaliophis, originally and now again placed in the family
Boidae, were also included in this family for some time (e.g., Goin, Goin & Zug 1978).
Central America, South America, West Indies.
Turks & Caicos Islands.