The systematics and external morphology of the southern African family Prototheoridae are reviewed. A single genus, Prototheora, is recognized, with the former genus Metatheora synonymized. Eleven species are recognized, including five new species: angolae, biserrata, drackensbergae, geniculata, and merga. In addition, two possibly new species represented only by female specimens are described but not named. A key to the species of Prototheora is provided, as well as a preliminary analysis of their relationships. The family is considered to be one of the most basal lineages in the Hepialoidea and can be partially destinguished from related families by several plesiomorphic characters including the retention of three segmented maxillary palpi (plesiomorphic within Hepialoidea), simple antenna, generalized leg structure with a complete set of tibial spurs (0-2-4), and a single row of abdominal spines on A3-7 of the pupa. Possible synapomorphies involve the lateral sclerotization of the suspensorium and the extreme development of a conjugal process from sternum IX of the female which may lock into a conjugal pouch usually formed by the male trulleum and juxta. The family occurs predominantly within two highly divergent, South African floristic zones, the Capensis, or Fynbos dominated Cape Flora, and the southern Afromontane zone, characterized by mostly temperate, evergreen forests. Most species occur within the Capensis, and all but three (P. angolae from central Angola and P. drackensbergae and parachlora from Natal) are restricted to Cape Province, mostly in or south of the Cape Folded Belt mountain ranges. Their life history remains unknown.