Inostrancevia is an extinct carnivorous therapsid genus, containing the largest gorgonopsians, which are best identified by their saber-tooth-like canine teeth.
Description[]
Inostrancevia was a large bodied, but agile predator. The humerus and femur of the animal are relatively elongated, suggesting that Inostrancevia was had proportionally longer limbs and was more cursorial than other gorgonopsids. Its front limbs are heavily built, possessing a robust and wide humerus. Inostrancevia's scapula is unlike any other known gorgonopsids with the fact that it is largely expanded, yet pretty narrow and plate-like. Inostrancevia's skull is equally as well built. Analyses show that the jaws of Inostrancevia were able to open a large amount, as opposed to a smaller gape in contemperary gorgonopsids like Sauroctonus. Similar to multiple other gorgonopsids, Inostrancevia had strongly developed canine teeth, with the ones on the upper jaw reaching up to 15 cm (5.9 in) long, the root corresponding half of the length of each canine tooth. Inostrancevia's dentition is comparable to those of saber-tooth cats like Smilodon or other mammals with similar characteristics.
Paleobiology[]
Hunting tactics[]
One of the most recognizable characteristics of gorgonopsians are the presence of big, sharp canine teeth on both the top and lower jaws. How they used these deadly weapons is debated, bite forces of saber-toothed predators like Inostrancevia, using 3D analyses, were determined by Lautenschlager et al. to find answers. Their discoveries say that, despite the morphological convergence amongst saber-toothed predators, there was a variety of possible techniques for killing. The similarly sized gorgonopsid Rubidgea had a bite force of 715 newtons. Although lacking the jaw strength needed to crush bones, the analysis revealed that large bodied gorgonopsids had stronger bite forces than most saber-tooth predators. This study also found out that Inostrancevia's jaw was capable of opening up wide, perhaps letting Inostrancevia deliver a deadly bite similar to the hypothesized killing technique of Smilodon.
Paleoecology[]
Inostrancevia was the apex predator of its environment, coexisting with other notable animals like Scutosaurus and Vixaxosaurus which were most likely its prey.