Phalanx bone and far phalanges of the fourth and fifth toes are often fused together (symphalangism). The phalanges of the hand are commonly known as the finger bones. The phalanges of the foot differ from the hand in that they are often shorter and more compressed, especially in the proximal phalanges, those closest to the body. A phalanx is named according to whether is are proximal, middle, or distal and its associated finger or toe. The proximal phalanges are those that are closest to the hand or foot. In the hand, the prominent, knobby ends of the phalanges are known as knuckles.
Diandongosuchus The astragalus and calcaneum bones of the ankle fit together like a ball-and-socket, a feature that confirms "Diandongosuchus" as a pseudosuchian. Some of the phalanges or toe bones are missing in ZMNH M8770, but the metatarsals are present and have unique proportions among Triassic archosaurs in which the fourth is longer than the third. A phylogenetic analysis conducted by Li "et al." (2012) in the original description of "Diandongosuchus" showed that it was the most basal member of a clade called Poposauroidea, which includes mostly terrestrial pseudosuchians such as the bipedal "Poposaurus" and the sail-backed "Arizonasaurus". It was found to