The genus Oligoxystre was originally established in 1924 for O. auratum Vellard 1924 from southern state of Goiás, Central Brazil. Today, the genus includes seven species: O. auratum, O. caatinga Guadanucci 2007, O. bolivianum (Vol 2001), O. tucuruiense Guadanucci 2007, O. rufoniger Guadanucci 2007, O. dominguense Guadanucci 2007, and O. diamantinensis Bertani et al. 2009. Oligoxystre mineirum new species, from the Atlantic forest domain is described here. The cladistic analysis resulted in a single tree: (O.caatinga (O.mineirum ((O.tucuruiense O.rufoniger) (O.diamantinensis (O.bolivianum O.dominguense))))). According to the area cladogram obtained, it is possible to draw the following conclusions: the origin of the Cerrado fauna is monophyletic; the occurrence of two sympatric species in Caatinga is due to different events; and the diversity of Oligoxystre in Serra do Espinhaço (O. rufoniger, O. diamantinensis and O. mineirum) is probably the result of the contact of the typical fauna of each bioma (Cerrado, Caatinga and Atlantic Forest).