Hesperonychus (meaning "western claw") was a small, carnivorous dinosaur. It was a member of the family Dromaeosauridae, along with its larger relatives Deinonychus and Velociraptor. There is one described species, Hesperonychus elizabethae. The type species was named in honor of Dr. Elizabeth Nicholls of the Royal Tyrell Museum of Paleontology who collected it as a student in 1982. It is known from fossils recovered from the lowermost strata of the Dinosaur Park Formation of Alberta, dating to the late Cretaceous (Campanian stage) about 76.5 million years ago. Though known from partial remains, Longrich and Currie estimated its total length at under one meter and weight at about 2 kilograms, making it the smallest carnivorous dinosaur known from North America.