Twenty-one, probably endemic, new species of Euptyctima from rainforest in Tasmania are described: two belonging to the Euphthiracaroidea and 19 to the Phthiracaroidea. Five species of Phthiracaroidea, recently described from continental Australia by the first author, were also found (Austrophthiracarus scopoli, A. sellnicki, Notophthiracarus alienus, N. flexiloquus and N. schusteri), as were four species of Eupththiracaroidea recently described from New Zealand (Oribotritia contortula, Microtritia contraria and M. glabrata) and a new but undescribed species of Oribotritia from New Caledonia. No species were found that had been recorded from outside the Australian biogeographic region: the only other species not previously recorded from Australia or New Zealand was Hoplophthiracarus montigenus Niedbala, originally described from Papua New Guinea and possibly of Gondwanan distribution. The likelihood of the high degree of endemism of the Tasmanian euptyctime fauna is discussed in the context of current concepts in the biogeography of oribatid mites.