Piatnitzkysaurus

Phylogeny: Dinosauria > Saurischia > Theropoda > Neotheropoda > Tetanurae > Megalosauroidea (?) > Piatnitzkysauridae

Overview: So far, there are two known fossil specimens of Piatnitzkysaurus, from both a subadult and probable adult, both represented by partial skeletons. These remains were found within Argentina’s Cañadón Asfalto Formation during the mid to late 1970’s. Described by the renowned Argentine paleontologist José F. Bonaparte, the generic name of Piatnitzkysaurus is meant to honor the geologist Alejandro M. Piatnitzky. Piatnitzkysaurus would go on to become the namesake of its own family, the Piatnitzkysauridae, which may contain other notable taxa like Marshosaurus and Condorraptor. Members are mainly known from either South or North America, though a genus from China may also belong to the family according to some studies. Piatnitzkysaurid fossils are mainly known from the Early to Late Jurassic.

According to its remains, Piatnitzkysaurus wasn’t a particularly large theropod. It measured four to five meters long, so it could be considered medium-sized. Asfaltovenator, another theropod from the Cañadón Asfalto, was a bit larger. Said genus may’ve been the region’s top predator, while Piatnitzkysaurus hunted smaller herbivores. None of the piatnitzkysaurids grew to be all that large, so this mid-tier role was their main strong suit. The same region was also home to sauropod dinosaurs like Patagosaurus. Adults of said genus were probably too large for this dinosaur to take down, at least when healthy. In many studies, the Piatnitzkysauridae is placed within the larger superfamily Megalosauroidea, making them related to Megalosaurus. Some recent studies suggest they were closer to Allosaurus, in the superfamily Allosauroidea.