Most of the dinocephalian fossils are limited to bones from the Upper Permian and are primarily found in Russian and South African deposits, with some from North America. However, it is assumed that they did in fact inhabit larger areas of Pangea.
The table below shows the known fossil record of the dinocephalians along with the other main groups of the therapsids and pelycosaurs. The lines linking the groups denote possible evolutionary relationships. Click on the image to enlarge it.
Geological timescale showing the dinocephalia to have a fossil record ranging from the Late Permian until their extinction towards the end of the Permian. Image constructed using information from Macmillan, 1988 (see Literature page).