A new species of Isotomidae (Collembola) was collected from submerged stones on the edge of nine lakes on Tasmania's Central Highland Plateau. Because it did not comply fully with the characters of any existing genus, a new genus, Chionobora gen. n. is erected for it here. An Antarctic species, Desoria klovstadi (Carpenter), has characters which conform with the new genus so is formally transferred to the new genus here. The Antarctic Continent and Tasmania were last in proximity 60 million years b.p. so it is suggested both species are relicts persisting in probable ice-free refugia during glacial cycles. Gut contents of specimens of the new species exclusively contained diatoms in various stages of digestion and the species appears to graze on aquatic macrophytes, a feeding habit not recorded before for Collembola. We note the high numbers of endemic invertebrate taxa of restricted distributions in cold habitats of southern regions compared to warmer regions and stress their conservation values and threats to their populations.
The taxonomic status of the subgenera of Lepidocyrtus Bourlet is confused. Currently ten subgenera are recognised but their separation, using the existing set of diagnostic characters, is not clear. Collections over the last forty years have shown that species of Setogaster Salmon, originally described as a genus (Trichogaster Handschin) and currently considered a subgenus of Lepidocyrtus, are common and widespread in Australia. The diagnostic characters of Setogaster, as given by Handschin, are: 1) the basal mucronal spine with spinelet; 2) lack of scales on antennae, legs, ventral tube and dorsal region of manubrium; and, for some species, 3) tufts of long filaments laterally on abdomen III. These three diagnostic characters for Setogaster are shared with some other subgenera, making their delimitation unclear. We provide here an array of new characters that are associated with Handschin's characters which separate Setogaster from all European species of the subgenera Lanocyrtus and Lepidocyrtus s. str. On this basis we define subgenus Setogaster more in detail, redescribe some species in the subgenus, corroborate the presence of the subgenus in many Australian localities, and confirm three records of exotic, introduced species in Australia. Lepidocyrtus nigrofasciatus Womersley, Lepidocyrtus praecisus Schott, and the Hawaiian Lepidocyrtus kuakea Christiansen & Bellinger, are placed in Setogaster subgenus; Lepidocyrtus (Trichogaster) pallida Salmon from Singapore is placed in the subgenus Acrocyrtus; Merapicyrtus Yoshii & Suhardjono is considered a synonym of Setogaster.