Allosaurus jimmadseni

†Allosaurus jimmadseni was a newly recognized species of †Allosaurus from the Late Jurassic (~157-152 Ma) Morrison Formation of Utah, USA. About 8m long, it predates and is distinct from †A. fragilis in skull morphology. Named by Chure and Loewen in 2020, it was based on an extraordinarily complete skull from Dinosaur National Monument, revealing new details of allosaurid cranial evolution.

Diet & Feeding

Carnivore

Allosaurus jimmadseni was a meat-eating predator. Carnivorous dinosaurs were active hunters or scavengers, equipped with sharp teeth and claws for catching and consuming prey. They occupied the top of the food chain in their ecosystems.

Time Period

Jurassic Late Mesozoic Era

Allosaurus jimmadseni lived during the Jurassic Late period of the Mesozoic Era, approximately 161.5 to 145.0 million years ago.

One of the most iconic periods for dinosaurs. Giant sauropods like Brachiosaurus and Diplodocus roamed alongside predators like Allosaurus. Archaeopteryx, the earliest known bird, appeared. The Morrison Formation preserves an extraordinary fossil record from this time.