Archaeornithomimus (Greek for "ancient bird mimic"); pronounced ARE-kay-OR-nith-oh-MIME-us
Plains of Asia
Middle Cretaceous (110-100 million years ago)
Size and Weight:
About 10 feet long and 100 pounds
Small, narrow head; light build
Sometimes, the dinosaurs with the longest names are the ones about that paleontologists know the least about. That's certainly the case with Archaeornithomimus, an ornithomimid ("bird mimic") from the middle Cretaceous period that was probably ancestral to the more well-known Ornithomimus. As you might expect, given their evolutionary relationship, Archaeornithomimus was comparatively less specialized than its famous descendant, with a much more slender build. Like other ornithomimids, Archaeornithomimus was probably omnivorous, fast enough to both chase down small animals and avoid larger predators.