ornithosuchians
Ornithosuchians were a group of archosaur reptiles that lived during the Triassic period. They are classified within the order Ornithosuchia and are notable for their unusual combination of features. Ornithosuchians possessed a semi-erect stance, meaning they could walk on either two or four legs. Their hind limbs were generally more robust than their forelimbs. A distinctive characteristic was their pelvic structure, which had a reversed pubis, a feature also found in birds, although this is considered a case of convergent evolution rather than direct ancestry.
The skull of ornithosuchians was also somewhat unusual. They had large supratemporal fenestrae, openings in the