A new genus, Birabenella, is erected for three new soft-bodied oonopid species from Coquimbo Region, Chile (B. homonota, the type species, B. elqui, and B. pizarroi) and one from Catamarca Province, Argentina: B. argentina (Birabén, 1955), here transferred from Oonopinus Simon. The new genus is supported and diagnosed by the tarsal claws with one row of teeth, and by the stout and flattened setae on the dorsum of the abdomen. The thickened anterior wall of the posterior receptacle in female genitalia, and the ventral digitiform projection on the bulb of the male palp are also probable synapomorphies.