Abstract

Parasarus Ruz, 1993 comprises small black bees (3-5 mm long) endemic to xeric regions of South America, mainly along of the Andean Cordillera. Prior to this study, the genus included only the type-species P. atacamensis Ruz, 1993 (from northern Chile) which has mesoscutum strongly reticulated and inner hind tibial spur curved apically. In this paper, a taxonomic revision of Parasarus is presented and two new species are described: P. specularis sp. nov. (from central to northwest Argentina) diagnosed mainly by pygidial plate of female extremely acute apically and labral plate yellow in male; and P. spiniventris sp. nov. (only recorded from central portion of Chile) diagnosed by antennal socket below middle of face, subantennal area as long as broad, metapostnotum smooth, and sternum 3 of male with a tuft of stiff hairs. The morphological variation related to the type-species was studied and not considered sufficiently to recognized distinct species into P. atacamensis. Distribution maps, floral associations, key to species of the genus, and illustrations of general external morphology and genitalia are also provided.