The genus Acantholybas Breddin contains 4 species: A. kirkaldyi Bergroth (Tasmania); A. brunneus (Breddin) (New South Wales to southeast Queensland and New Zealand); A. longulus Breddin (Lombok and Sumbawa Islands, Indonesia); and A. steinbaueri Brailovsky (Java). A. kirkaldyi was known, until recently, only from the original description as the holotype (the only known named specimen) is lost. Following recollection of A. kirkaldyi from the type location, Tasmania, a revision of the genus was undertaken. Species redescriptions are given and neotypes and lectotypes designated for A. kirkaldyi and A. brunneus, respectively. Notes on biology are included for A. kirkaldyi and A. brunneus.