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Prefrontals and large postfrontals contiguous over orbit. A distinct preparietal in front of small parietal foramen. Temporal opening bounded above by united postorbital and squamosal, below by squamosal and jugal or squamosal only. Parietal region wide. A single vomer (? fused prevomers). No secondary palate; an ectopterygoid. No acromion on scapula; no cleithrum; coracoids relatively small; a large proatlas. Phalangeal formula primitive 2, 3, 4, 5, 3.

A group intermediate, according to Broom, between the Therocephalia and Anomodontia.

Middle and Upper Permian.

. Gorgonops Owen, Scymnognathus Broom, Cyniscodon Broom, Cerdognathus Broom, Scymnosaurus Broom, Gorgonognathus Haughton, Scylacognathus Broom, Scylacops Broom, Galesuchus Haughton, Ictidomorphus Broom, Aloposaurus Broom, Aelurosaurus Owen, Cynodraco Owen, Tigrisuchus Owen, Arctosuchus Broom, Arctognathus Broom, Arctops Watson, Theriodesmus Seeley, Asthenognathus Broom, South Africa. Inostrancevia Amalitsky, Russia.

. Middle and Upper Permian. Ictidorhinus Broom, South Africa.

. Lower Triassic. Burnetia Broom, South Africa.

A well-formed secondary palate; a median, unpaired vomer; single occipital condyle; the pterygoids extend to quadrates; no postfrontals; squamosal small; quadrate large; parietal foramen present or absent; strong incisors and grinding molars; large posterior palatine vacuities. No acromion on scapula.

Upper Triassic. Bauria Broom, Microgomphodon Seeley, Melinodon Broom, Sesamodon Broom, Aelurosuchus Broom, South Africa.