Rubidgeinae is a subfamily of advanced gorgonopsians. In 2016, it was revised in detail by Christian Kammerer, and of 36 species already described, 9 were recognized as distinct and valid. Between them, 7 are remarkable together for a reason: they lived in the same place and time, in the Karoo Basin (South Africa) during the Late Permian. They are Smilesaurus ferox, Aelurognathus tigriceps, Sycosaurus laticeps, Leontosaurus vanderhorsti, Dinogorgon rubidgei, Rubidgea atrox and Clelandina rubidgei.
7 large predators (with skulls of no less than 30 cm, with some exceeding 40 cm) sharing an ecosystem imply some interesting factors, such their possible specializations to occupy different niches and decrease the competition, making the coexistence possible.
Rubidgea atrox gives the name to the Rubidgeinae subfamily, and is its largest member. In fact, it is not just the largest rubidgeine, but is also one of the largest gorgonopsians in general, rivaling only Inostrancevia.