A new species of the Late Triassic aetosaur Desmatosuchus (Archosauria: Pseudosuchia)

Reanalysis of known armor of the stagonolepidid (aetosaur) Desmatosuchus has shown distinct differences in the lateral armor among individuals known from Carnian and Norian age rocks in the southwestern United States. Combined with previously reported cranial differences it is apparent that Norian specimens of Desmatosuchus represent a species distinct from the type species Desmatosuchus haplocerus and are described herein as Desmatosuchus smalli n. sp. D. smalli is known solely from Norian age rocks, whereas D. haplocerus is known only from Carnian age rocks. The separation of Desmatosuchus into distinct Carnian and Norian species suggests some biostratigraphic utility for these taxa.