Dinosaur

The Dinosaurs are a diverse group of prehistoric reptlies that once roamed Earth in the Mesozoic Era.

Biology
Dinosaurs are characterized in numerous shapes, sizes and forms; sauropods (massive cuadrupedal long-necked herbivorous dinosaurs), theropods (bipedal carnivorous dinosaurs), ceratopsids (cuadrupedal horned frilled herbivorous dinosaurs), ornithopods (bipedal herbivorous dinosaurs), etc.

In popular culture
Extraterrestrial life forms similar to, and/or identified as dinosaurs include the following.
 * In the Carnivores universe, appear not only alien dinosaurs, but also alien prehistoric mammals.
 * The Vaxasaurians from Ben 10 universe, resemble anthropomorphic sauropods.
 * Triassians are a race highly evolved dinosaurs from the comic book Dinowars.