Manga by Masashi Tanaka.
Gon somehow survived the extinction of his fellow dinosaurs and interacts with palaeolithic animals.
Gon's exact saurian species is never delved into. He vaguely resembles an outdated depiction of a generic carnosaur in a tripod stance, only about the size of a small dog. He is an omnivore with an enormous appetite. He possesses enormous power and endurance for his size, his feats of strength including supporting his own weight with his jaws, to being able to partially lift a fully grown African Elephant. His scaly hide is almost impenetrable, being able to shrug off the bites of larger predators.
Gon's intelligence seems to fluctuate in each adventure, ranging from total cluelessness (such as failing to notice a birds nest on his head for weeks), to strategic cunning (using a lion as a beast of burden to capture prey).