ABSTRACT: A new genus of onchidiid slugs, Wallaconchis Goulding & Dayrat, gen. n., is described, including ten species. Five species were previously described but known only from the type material: Wallaconchis ater (Lesson, 1830), W. graniferum (Semper, 1880), W. nangkauriense (Plate, 1893), W. buetschlii (Stantschinsky, 1907), and W. gracile (Stantschinsky, 1907), all of which were originally classified in Onchidium Buchannan, 1800. Many new records are provided for these five species, which greatly expand their known geographic distributions. Five species are new: Wallaconchis achleitneri Goulding, sp. n., W. comendadori Goulding & Dayrat, sp. n., W. melanesiensis Goulding & Dayrat, sp. n., W. sin
