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.
 * In the Ben 10 universe, The Vaxasaurians resemble anthropomorphic sauropods, the Pturbosaurians resemble anthropomorphic pterosaurs and the Kaosseffexx Ultimasauria resembles a tyrannosaurus/centipede hybrid.
 * Triassians from the comic book Dinowars, are a race highly evolved dinosaurs that use genetically-enginnered dinosaurs as war beasts.
 * The Triceratons are extraterrestial humanoid bipedal-triceratopses.