Overview

• Kostensuchus atrox was formally described in PLOS ONE on August 27, based on an articulated skull, jaws and partial skeleton unearthed near El Calafate, Argentina.
• Researchers estimate the animal reached about 3.5 meters in length and 250 kilograms in mass, placing it among the largest predators from the site.
• Anatomy including a high, broad snout, deep jaw‑muscle chamber and large serrated teeth indicates hypercarnivory and active terrestrial predation.
• The find is the first crocodyliform reported from the Maastrichtian Chorrillo Formation and marks the latest and southernmost record of peirosaurids.
• Its completeness offers new anatomical and phylogenetic data on broad‑snouted peirosaurids and expands the known predator guild in high‑latitude Gondwanan ecosystems just before the K–Pg extinction.