Hesperosuchus

Hesperosuchus Temporal range: Late Triassic, 220 Ma PreЄ Є O S D C P T J K Pg N ↓
Hesperosuchus agilis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	Crocodylomorpha
Family:	Ornithosuchidae
Genus:	Hesperosuchus
Species:	H. agilis
Binomial name
Hesperosuchus agilis

Hesperosuchus is an extinct genus of crocodylomorph reptile that contains a single species, Hesperosuchus agilis. Remains of this pseudosuchian have been found in Late Triassic (Carnian) strata from Arizona and New Mexico.Hesperosuchus was once believed to an ancestor of later carnosaurian dinosaurs due to similarities in skull and neck anatomy along with the presence of hollow bones. Now with further findings and research, Hesperosuchus is now known to be closer related to not dinosaurs but crocodilians instead.

At only about 4 to 5 feet in length, Hesperosuchus is a relatively small and lightly built pseudosuchian. It is very closely comparable to the different genera, Ornithosuchus woodwardia and Saltoposuchus longipes, which are both pseudosuchians as well. Hesperosuchus’ hind limbs are large and strong, while the forelimbs were smaller and much slenderer. This observation lead to the hypothesis that Hesperosuchus is indeed an animal expressing bipedality. It was found that when comparing the hind limbs of Saltoposuchus to those of Hesperosuchus, they are evenly as large and strong. The length of the extended hind limb in both genera are approximately equal to the length of the presacral vertebrae. Saltoposuchus was described by van Huene, and portrayed as a falcultative quadraped. It is believed that Hesperosuchus also practices both bipedialism and quadrapedalism. Though it is believed to be more often on two feet as the long slender hands looked as if it was adapted for grasping, which may be useful for food gathering, digging or defense. Five digits were found on both the hind limbs as well as the forelimbs. In order to counterbalance the weight of its body, Hesperosuchus is inferred to have had a relatively long tail. Since the caudal vertebrae aren’t completely restored, it is inferred based on similar archosaurians, that the tail contained somewhere around 45 caudal vertebrae. The strong hind limbs and overall light weight made Hesperosuchus very quick and able to move rapidly. This advantage of speed allowed for it to catch small prey and escape from larger predators.