River lion

The river lion was a name given to the dominant predator of Epsilon XVII by Starfleet. This animal was in danger of extinction until the tribble was introduced to this ecosystem. The new, ready supply of prey was much welcomed by this green, black and orange animal. This species was similar to a cat except for the cranial protuberances similar to antlers that come out of it's head. (SS New Worlds, New Civilizations (Second Chances (short story)))