Arizonasaurus

Arizonasaurus babbitti, live reconstruction

• North America ( Moenkopi Formation, Arizona)

• Arizonasaurus babbitti

Arizonasaurus ( " lizard from Arizona " ) is a genus of scoring to the basal archosaurs extinct Rauisuchia from the Middle Triassic of North America.

Samuel Paul Welles in 1947 published the first scientific description of the genus and its type species A. babbitti on the basis of a single maxillary bone from the Moenkopi Formation near Holbrook in the U.S. state of Arizona. By a further discovery of a complete about half the skeleton in 2002, the description of the animal and the systematic assignment could be clarified.

Fossil Description

The holotype of A. babbitti consists of a single bone of the left maxilla, which differed by a typically shaped triangular extension from other known species. In 2002, Dylan Rust in the formation a series of isolated Archosaurierknochen, including parts of the spine, the skull and pelvis, have been found. The parts were described in 2003 by Sterling J. Nesbitt as a about 50 percent preserved skeleton of a subadult individual of A. babbitti, where he turned out nearly identical maxillary bone.

Fund location

The fossil record of A. babbitti originate exclusively from the upper Moenkopi Formation in Arizona, USA. This is due to the presence of which must be an Temnospondyli Eocyclotosaurus and magnetostratigraphy to the Middle Triassic, more precisely on the Anisian before about 240 million years ago, dated.

System

A. babbitti could in which, however, most likely not monophyletic ' Rauisuchia ' and here in the Poposauridae or Ctenosauriscidae, a very closely related group are classified due to the finds of 2002. In the course of previous experiments, Arizonasaurus systematically classified, he had been assigned to different groups such as the dinosaurs, the Trilophosauridae, the Stagonolepididae, the Proterosuchia and also the Erythrosuchidae.