One final note on the Eodicynodon / Galeops sisterhood issue.
As reported earlier here and here, everyone else nested the dromasaur Galeops (Fig. 1) as the outgroup to the Dicynodontia with Eodicynodon (Barry 1974) at its base. However, by adding taxa, the large reptile tree nested Microurania at the base of the Dicynodontia + Venjukovioidea. Elsewhere Galeops nested as a derived dromasaur, having arisen from their common ancestor a sister to Stenocybus..
It would be great
to see Eodicynodon and Galeops to scale side-by-side for ready comparison, since they nest together in all traditional trees. Like Clark Kent and Superman, they have never been pictured together. So here they are (Fig. 1) for the first time.
but those details were by convergence and common ancestry with Stenocybus. And this origin appears to be distinct from all other therapsids (see below). Overall, a suite of traits nests Eodicynodon and Galeops apart. Likely they did not share the same niche. The large reptile tree found them to be “strange bedfellows” nesting together by default because better nesting partners were not included in analyses.
Anomodontia (dromasaurs + dicynodonts), according to Wiki, are derived from Dinocephalia. which also (according to Wiki) give rise to Theriodonts, which leads to mammals. That puts two plant-eating clades in the middle of a string of carnivores. Not good. Red flag.
On the other hand,
the large reptile tree nested anomodonts with Stenocybus, arising from Ophiacodon/Haptodus. The large reptile tree nested the rest of the therapsids with Nikkasaurus and Biarmosuchus arising out of Archaeothyris/Ophiacodon. Then both Dinocephalians and Theriodonts arise from Phthinosuchus and Eotitanosuchus, which really makes more sense, keeping the carnivorous line carnivorous and the herbivore line distinct.
The trouble is
Stenocybus, Microurania and Nikkasaurus are only known from skulls and, to my knowledge, have not been added to therapsid family trees. They need to be.
Barry TH 1974. A new dicynodont ancestor from the Upper Ecca. Annals of the South African Museum 64: 117-136.
Rubidge BS, King GM and Hancox PJ 1994. The postcranial skeleton of the earliest dicynodont synapsid, Eodicynodon from the Upper Permian of South Africa. Palaeontology 37(2):397-408.