Hoplopleura auliscomydis n. sp. is described based on specimens collected from Auliscomys micropus (Waterhouse 1837), from Collón Curá, Neuquén Province, Argentina. Descriptions are provided for the holotype male, female, first nymphal instar, external architecture of eggs (by scanning electron microscopy), and sites of oviposition, providing differences from its close relative Hoplopleura neotomydisCastro, González, and Cicchino, 1995. The geographical ranges of these 2 species are restricted to the Neuquén Province in Argentina. A key to the 9 species of the Hoplopleura travassosi species-group recorded in Argentina is also given.