Alectrosaurus was an Asian Theropod dinosaur that is related to Tyrannosaurus rex. It was a carnivore (meat-eater), and lived in what is today the Gobi desert in Mongolia and China, during late Cretaceous period, between about 83 and 74 million years ago.
Alectrosaurus was probably a maximum of about 17 feet (5 meters) long, and probably weighed somewhere between ½ ton and 1 ton. A number of details of the creature are currently unclear, because only partial fossil specimens have so far been found. Additionally, some paleontologists have suggested that Alectrosaurus may actually be a species of Albertosaurus.
The first fossil specimen of Alectrosaurus was discovered by George Olsen in 1923. It was named by Charles W. Gilmore in 1933. Literally translated from the Greek, "Alectrosaurus" means "unmarried lizard" - Gilmore, chose "unmarried" in the sense of "being alone" - at the time Alectrosaurus was discovered, it was thought to be quite unlike other Asian dinosaurs - although part of the reason was this was that a number of fossil bones from an unrelated dinosaur were initially also thought to belong to the animal.