Redondasuchus reseri is a Late Triassic (Rhaetian) aetosaur from the Redonda Formation of eastern New Mexico. It differs from all other aetosaurs except Typothorax by its paramedian scutes with ventral keels. It is the only Rhaetian aetosaur currently known from the United States and is an index taxon for the Apachean land-vertebrate faunachron. A cladistic analysis of the aetosaurs, utilizing both characters derived from armor and other skeletal information, indicates that two distinct grades of aetosaurs exist. There is a basal grade consisting of the paraphyletic assemblage of aetosaurus and (Stagonolepis + Aetosauroides), and an advanced grade consisting of the clade Neoaetosauroides + Redondasuchus + ((Longosuchus + Desmatosuchus) + (Paratypothorax + typothorax)).[1]
Description and species[]
Redondasuchus was first named with the description of the type species, R. reseri, in 1991.[1] R. reseri was named on the basis of isolated scutes found at Apache Canyon and Shark Tooth Hill in Quay County, New Mexico. R. rineharti was described in 2006 from several scutes and part of a right femur found from Apache Canyon.[2]
While other aetosaurs have scutes covered in pits and grooves that often form radial patterns, the scutes of Redondasuchus are densely covered in pits and lack any patterning. The dorsal paramedian scutes (those that line the back) are unique in that they are angled approximately 45°. In other aetosaurs, the scutes arc smoothly around the back from the midline to the lateral scutes that lie below them and run along the side of the animal.[2]
The dorsal paramedians of R. reseri are smaller than those of R. rineharti. In both species, each paramedian possesses a keel on the underside that extends from the medial edge (the edge near the vertebrae) to the flexed area of the scute.
Orientation of scutes and plagiarism allegations[]
References[]
 |
This article is a stub.
You can help the Fossil Wiki by expanding it. |