 They originated from the same general layer of rock, in the upper "Cistecephalus" Assemblage Zone of the Beaufort Group within the Karoo Supergroup.The "Cistecephalus" AZ has been dated to the Wuchiapingian stage of the Late Permian, between 256.2 and 255.2 Mya.Broom named the genus "Euchambersia", which he considered "the most remarkable therocephalian ever discovered", after the eminent Scottish publisher and evolutionary thinker Robert Chambers, whose "Vestiges of the Natural History of Creation" was considered by Broom to be "a very remarkable work" though "sneered at by many".