lack of material has led many paleontologists to reject it as a nomen dubium. A reassessment of the holotype UCMP 34498 of Camposaurus arizoniensis by Ezcurra and Brusatte revealed two autapomorphies, thereby firmly establishing this material as a valid genus and species. This analysis also demonstrated that Camposaurus is definitely a neotheropod, and based on phylogenetic analysis its closest known relative is Megapnosaurus rhodesiensis, because they share similarities in the tibia, and ankle. The synonymy with Coelophysis was found to be unsupported in 2017 when in a phylogenetic analysis by Ezcurra, Camposaurus was found to be in a clade with Meganosaurus, Segisaurus, and also Lucianovenator by Martinez & Apaldetti later that year. Distinguishing anatomical features A diagnosis is a statement of the anatomical features of an organism (or group) that collectively distinguish it from all other organisms. Some, but not all, of the features in a diagnosis are also autapomorphies. An autapomorphy is a distinctive anatomical feature that is unique to a given organism or group. According to Ezcurra and Brusatte (2011), Camposaurus can be distinguished based on the following features: the caudal ridge of the tibia articular surface on the fibula is prominent, taking the form of a sharp longitudinal ridge, the medial surface having a strongly developed, rostrally bowed, diagonal tuberosity the astragalus is without a strong cranial projection of the medial condyle of the astragalar body, resulting in a sub-rectangular astragalar body in the distal aspect, and a ventral margin that is incipiently concave in the cranial aspect References Coelophysoids Late Triassic dinosaurs of North America Triassic Arizona Paleontology in Arizona Fossil taxa described in 1998 Taxa named by Spencer G. Lucas Taxa named by Robert M. Sullivan Taxa named by Martin Lockley