A new species of Ananteris Thorell, 1891 (Scorpiones, Buthidae C. L. Koch, 1837) is described from rain forest in the area of the Ouarimapan river in the South of French Guyana. The new species Ananteris sabineae n. sp. is related to Ananteris pydanieli Lourenço, 1982. The two species can readily be distinguished by: 1) much paler pigmentation of pedipalps and legs in A. sabineae n. sp., with only diffused spots; 2) darker pigmentation of carapace and tergites in A. sabineae n. sp., with less conspicuous yellow spots; 3) differences in cheliceral dentition: in A. sabineae n. sp. the movable finger has two basal teeth, whereas in A. pydanieli only one is present; the median and basal teeth of the fixed finger are more conspicuous in A. pydanieli. This is the fourth species of Ananteris described from French Guyana. The total number of species in the genus is now raised to 24.
Arachnida, Scorpiones, Buthidae, Ananteris, French Guyana, neotropics, new species.