142 species of which 76 (53.5%) are endemic -
13 genera of which 2 (15.4%) are endemic
(as of December 31st, 2018).
Until recently, all species of this family, except
Rhinoleptus koniagui, were included in the genus
Leptotyphlops. Adalsteinsson, Branch, Trape, Vitt & Hedges (2009) revised the systematics of the family, recognizing twelve valid genera.
Wallach (2003) recommended the restriction of the name Worm Snakes to the family Leptotyphlopidae, whereas the family
Typhlopidae should be called Blind Snakes. Although the latter suggestion has been followed in most publications, both since and before Wallach's suggestion, the former has not. Currently, most works have retained the name Thread Snakes for the familiy Leptotyphlopidae (e.g., Crother (ed.) 2008; Liner & Casas-Andreu 2008), presumably because the name Thread Snakes has only been used for this family, whereas Worm Snake has been used for both, as well as for other snake genera (e.g.,
North America, Central America, South America, West Indies, Africa, Middle East, SW. Asia.
Central African Republic,
Trinidad & Tobago,
United Arab Emirates,