Herrerasaurus
From Tardis Wiki, the free Doctor Who reference
The Herrerasaurus was a type of theropod dinosaur. They were small predators, only 5 feet long and 300 pounds, but fast and very vicious. They had excellent vision and hearing, as well as a powerful sense of smell.
The herrerasaurus was one of the species that the Silurians brought back from extinction after they took over in a parallel world. Packs of Herrerasaurus were used by the Silurians in their hunts, being sent first to tear apart the prey. They were trained by use of flute signals, and would become fearless during the hunt. They would also be telepathically controlled by the Silurians for more complex tasks. (NA: Blood Heat)