Crurotarsi

The Crurotarsi are a group of archosauriformes represented today by the crocodiles, alligators, caimans and gharials (and possibly birds, see below) that also includes many extinct forms. The name is derived from the Latin words crus and tarsus; it refers to the specialized articulation between crus and tarsus—specifically between fibula and calcaneum—present in the skeletons of suchians and phytosaurs, with a hemicylindrical condyle on the calcaneum articulating against fibula.