Parasuchus

Parasuchus hislopi (Huxley 1870) Late Triassic ~210mya, 2.5 m. long. Parasuchus was a sister toPaleorhinus. Both were derived from a sister to Proterochampsa and Youngoides RC91 and phylogenetically preceded Mystriosuchus (see below).

Distinct from Proterochampsa, the premaxilla of Parasuchus was drawn out as a narrow rostrum. The antorbital fenestra was bordered by a fossa. The orbit was raised to the top of the skull. The mandible had a fenestra.

The cervical centra were taller than long. The tail had tall neural spines and was only slightly longer than the presacral series.

The coracoid had a deep embayment and was relatively small.

The pelvis had a minor anterior process. The femur was sigmoidal. The calcaneum had a heel that was oriented posterolaterally, then turned posterormedially. Pedal digit 4 was shorter than 3 due to reduced phalanges. Metatarsal 5 was hook-shaped.

A row of osteoderms lined the vertebral series.

Recently Irmis et al. (2007) and Nesbitt (2009) nested parasuchians as the closest taxon to pterosaurs That is ridiculous and no one has provided a list of characters linking parasuchians to pterosaurs. Parasuchus had tiny hands, a long snout, osteoderms and a flat skull among dozens of other traits not found in basal pterosaurs. Rather, the fenestrasaurs, Cosesaurus, Sharovipteryx and Longsiquama, provide a series of traits documenting a gradual evolution of pterosaur characters.

Mystriosuchus planirostris (von Meyer 1863, originally Belodon, Fraas 1896) Late Triassic ~210 mya, ~4 m in length was considered a fish-eater and more aquatic than other parasuchians.

Distinct from Parasuchus, the skull of Mystriosuchus had a longer, lower rostrum with a more posteriorly placed naris, directly over the antorbital fenestra. The tail was longer. The pelvis was lower and longer. The femur was relatively longer.

von Huene F 1915. On reptiles of the New Mexican Trias in the Cope Collection. Bulletin of the American Museum of Natural History 34: 485-507.

Huxley 1870. On the Classification of Dinosauria, with observations on the Dinosauria of the Trias. Quarterly Journal of the Geological Society 26: 32-51.

Irmis RB, Nesbitt SJ, Padian K, Smith ND, Turner AH, Woody D and Downs A 2007. A Late Triassic dinosauromorph assemblage from New Mexico and the rise of dinosaurs. Science 317 (5836): 358–361. doi:10.1126/science.1143325. PMID 17641198.

Nesbitt SJ, Irmis RB, Parker WG, Smith ND, Turner AH and Rowe T 2009. Hindlimb osteology and distribution of basal dinosauromorphs from the Late Triassic of North America. Journal of Vertebrate Paleontology 29 (2): 498–516. doi:10.1671/039.029.0218

Westphal F 1976. Phytosauria, in O Kuhn (ed.), Handbuch der Palaeoherpetologie Teil 13: Thecondontia, Gustav Fisher-Verlag, Stuttgart.

wiki/Phytosaur
wiki/Mystriosuchus

Euarchosauriformes

Pararchosauriformes

Choristodera