1 Order †Thecodontia Owen, 1859 see Division Archosauria Cope, 1869 2 Order Crocodylia Wagler, 1830 - crocodiles 3 Order †Pterosauria Kaup, 1834 - pterosaurs 4 Order †Saurischia Seeley, 1887 see Clade Saurischia Seeley 1888 [Gauthier, Langer, Novas, Bittencourt & Ezcurra 2020] 5 Order †Ornithischia Seeley, 1887