Credit: Julius Csotonyi for the Smithsonian Institution
An artistic interpretation of a newly discovered extinct species of lizard-like reptile belonging to the same ancient lineage as New Zealand’s living tuatara. The newly discovered Opisthiamimus gregori preys on a now-extinct water bug (Morrisonnepa jurassica), while in the background the predatory dinosaur Allosaurus jimmadseni guards its nest. The scene is the¬ floodplain of a river in Late Jurassic Wyoming, approximately 150 million years ago. A team of scientists describe the new species, which once inhabited Jurassic North America about 150 million years ago alongside dinosaurs like Stegosaurus and Allosaurus, in a paper published today in the Journal of Systematic Palaeontology. In life, this prehistoric reptile would have been about 16 centimeters (about 6 inches) from nose to tail and would fit curled up in the palm of an adult human hand. The discovery comes from a handful of specimens including an extraordinarily complete and well-preserved fossil skeleton excavated from a site centered around an Allosaurus nest in northern Wyoming’s Morrison Formation.