The dinosaur’s remains were found in the roughly 125-million-year-old rock of the Cedar Mountain Formation southeast of Green River, Utah, and collected under permit from the Bureau of Land Management and placed into the collections of the Natural History Museum of Utah in Salt Lake City.
It was originally thought to be a meat-eating dinosaur, supported by the fact that other theropods (such as the famous Utahraptor) have been found in the same rocks. Some of Martharaptor’s remains, especially the scapula and claws resemble the pot-bellied, bipedal dinosaurs called therizinosaurs. The well-known therizinosaur Falcarius utahensis was found very close by in slightly older rocks. These omnivorous and herbivorous dinosaurs stand out in having long necks and large hand claws.
Until a complete skeleton is found, the Martharaptor greenriverensis will remain an enigma. And possibly, Hayden herself will make the next discovery.
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