Genus Alacran Francke, 1982

Type species.— Alacran tartarus Francke, 1982, by monotypy.

Diagnosis. Alacran is the only genus of Typhlochactidae with incremental neobothriotaxy: the patella has 26– 27 trichobothria, including three on the ventral aspect (other genera in the family have two ventral trichobothria) (Prendini et al., in press, Table 3); and the chela has 29 trichobothria, including five on the ventral aspect (other genera have four) (Prendini et al., in press, Table 4). All the trichobothria are the same size; there are no “petite” trichobothria in this genus (Vignoli & Prendini, 2009). The two known species are eyeless troglobites from caves in the state of Oaxaca, Mexico.