Paleontologists have found a new species of crocodilians, Kostensuchus atrox, measuring almost 12 feet (3.5m) and weighing roughly 250kg. It inhabited southern patagonia during the later Cretaceous period, around 70 million years ago.
Kostensuchus, described in a paper published last month, had a powerful and wide jaw, which contained big teeth. This would have made it capable of devouring even medium-sized dinosaurs.
Skull and jaw of Kostensuchus atrox Photographs in (A) right lateral, (B) dorsal, and (C) ventral views. Interpretative drawings in (D) right lateral, (E) dorsal, and (F) ventral views. Scale bar 5 cm. DOI: https://doi.org/10.1371/journal.pone.0328561.g002
“This specimen is one of the best preserved and anatomically informative peirosaurid crocodyliform yet recorded“, the researchers wrote. “And the most complete representative of robust, broad snouted members of this clade“
The fossil gives clues about life in Patagonia, 70 million years ago
The fossilized skull and bones of Kostensuchus were found in the Chorrillo Formation, about 30 km south-west of the hiking town of El Calafate. Kostensuchus inhabited a Patagonia that could be described as a a freshwater ecosystem. It had a temperate to warm climate with seasonal humidity. And Kostensuchus lived alongside a diverse fauna of dinosaurs, mammals, and other vertebrates.
The broad and high snout of Kostensuchus with large and strong teeth, along with strong forelimbs suggests that it was capable of subduing large prey. “These features imply that Kostensuchus played the role of a top predator within this end-Cretaceous ecosystem.“, the researchers concluded.
Skull and jaw of Kostensuchus atrox Photographs and interpretative drawings in (A-B) anterior and (C-D) posterior views. Scale bar 5 cm. https://doi.org/10.1371/journal.pone.0328561.g003
The fossil also helps scientists understand crocodyliform clades
The discovery of Kostensuchus atrox considerably expands the knowledge about the anatomy of broad-snouted peirosaurids (the crocodilian group to which it belongs). This group was previously known from extremely fragmentary remains from South America and Madagascar.
Further, the new anatomical information provided by Kostensuchus sheds light on both, the similarities and differences, between broad-snouted peirosaurids and baurusuchids, which is the other crocodyliform clade that independently evolved into apex predators during the Cretaceous of Gondwana.