Torosaurus

Torosaurus is a genus of large, herbivorous ceratopsid dinosaurs that lived in North America during the Late Cretaceous, around 68 to 66 million years ago. It is known for a very large skull and an elongated frill that bears two large openings (frill fenestrae). Like other ceratopsids, Torosaurus possessed horns and a beaked mouth, and its frill and horns were likely used for display, species recognition, and possibly defense.

Size and anatomy: Torosaurus specimens indicate a robust, quadrupedal animal with a long body. Estimates place total length around 7 to 9 meters, and a body mass several tons. The defining feature is the tall, extended frill at the back of the skull with the distinctive openings, along with horned brow ornamentation typical of ceratopsids.

Discovery, distribution, and taxonomy: Fossils attributed to Torosaurus have been found in western North America, including what is now Alberta and surrounding regions. The genus includes species such as Torosaurus latus. For much of the 20th century it was treated as a distinct genus, but in later decades a hypothesis proposed that Torosaurus may represent the mature form of Triceratops. More recent analyses generally treat Torosaurus as a valid genus, though the relationship between Torosaurus and Triceratops remains a topic of ongoing discussion.

Paleoecology and significance: Torosaurus inhabited floodplain and forested environments near the end of the Cretaceous, coexisting with other herbivores and predators. Its distinctive skull and frill contribute to understanding ceratopsid evolution, growth, and the diversity of ceratopsids in North American ecosystems at the twilight of the dinosaur era.