Carnotaurus (Carnotaurus sastrei) belongs to the theropod group of dinosaurs and lived approximately 72 to 69 million years ago in what is now Argentina. Its name, meaning "meat-eating bull," aptly describes this predator. The first fossils of Carnotaurus were discovered in 1984, and subsequent discoveries have provided scientists with crucial insights into the evolutionary history of theropods. The skeleton that was unearthed proved to be nearly complete and even retained some preserved skin.

Carnotaurus, a substantial theropod dinosaur, measured approximately 26 to 30 feet (8 to 9 meters) in length and weighed an estimated 4,000 to 5,000 pounds (1,800 to 2,300 kilograms). It was characterized by its sturdy build, short arms, and a unique pair of forward-facing horns above its eyes. The skull, vertebrae, and forelimbs of Carnotaurus pointed to its highly specialized nature.

What truly sets Carnotaurus apart are its cranial features. Its snout was short, jaws deep, and it bore a pair of horns above its eyes, likely utilized for display or combat between individuals. One of its most extraordinary attributes was its significantly reduced and vestigial forelimbs, with only two small fingers, contrasting sharply with its large and powerful hind limbs. Despite its formidable appearance, these short arms probably played a limited role in its hunting strategy.