The Glacidorbidae, a family restricted to the Gondwanan realm (Tasmania, southeastern and southwestern Australia, and southern Argentina and Chile), previously included five genera with 20 identified species; 19 of them are Australian, with one genus and species, Gondwanorbis magallanicus (Meier-Brook & Smith, 1976), from South America. Here we describe two new species of Gondwanorbis: Gondwanorbis fueguensis n. sp. from the freshwater gastropods province of Southern Patagonia (Argentina) and Gondwanorbis tricarinatus n. sp. from Chile, and a new genus and species from the freshwater gastropods province of northern Patagonia (Argentina), Patagonorbis nahuelhuapensis n. sp and n. gen. [ABSTRACT FROM AUTHOR]