Piatnitzkysaurus (“Piatnitzky’s lizard”, for the Argentinean geologists Alejandro Matveevich Piatnitzky, who was born in Russia, and Miguel Flores) lived during the Middle Jurassic, about 160 million years ago. This makes Piatnitzkysaurus slightly older (in geologic terms!) than Allosaurus, who lived in North America around 145 million years ago. Piatnitzkysaurus had longer arms like Allosaurus and is thought to be a relative of his. The skeleton of Piatnitzkysaurus was found in the Cañadon Asfalto Formation in Chubut Province, Patagonia, Argentina.
