The Phenacodus was a mammal placental condylarths order. As features an animal was relatively small and light. His skull was too small and his back arched. It was also one of the first animals to present hooves. It was estimated that as much herbivore carnivore. Etymology: Age: Paleocene to Eocene (55 million years) Location: North America. Height / Length: 0.5 m long. Weight: Food: Omnivore.