They reached their highest diversity in the Cistecephalus and Daptocephalus assemblage zones of the Beaufort Group in South Africa.

Rubidgea was a heavily-built, large-bodied apex predator, and sported a thick skull with long, sabre-like canines.

[10][11] The Rubidgeinae group as a whole were some of the largest gorgonopsians known to have lived, only outsized by Inostrancevia, and are characterised by their robust skeletal features, particularly their skulls which are heavily-pachyostosed.

[22] Nochnitsa Viatkogorgon Suchogorgon Sauroctonus Pravoslavlevia Inostrancevia Phorcys Eriphostoma Gorgonops Cynariops Lycaenops Smilesaurus Arctops Arctognathus Aelurognathus Ruhuhucerberus Sycosaurus Leontosaurus Dinogorgon Clelandina Rubidgea Numerous therapsid species, including rubidgenae gorgonopsids, are used as biostratigraphic markers in other African Basins, such as the Upper Madumabisa Mudstone Formation of Zambia, and the Chiweta Beds of Malawi.

[23] Rubidgea fossils have been recovered from the Usili Formation of Tanzania, indicating biostratigraphic correlation with upper Permian-aged deposits in South Africa.