Capellan power-cat

A Capellan power-cat is a large feline mammalian lifeform native to Capella IV. It was capable of generating electrical discharges of significant age.

Background
About the size of an Earth bear, and able to run as fast as a cheetah, the power-cat was described as untamable and the most fierce creature in known space. Its electrical discharges had a range of 20 feet and could exceed 2,000 volts. 

Power-cats inhabit Capella IV's northern deserts and are noted for being vicious, aggressive carnivores who strongly defend their offspring. Power-cats are smart and elusive. 

Power-cat eyes were split vertically with dark-colored pupils, similar to an Earth lynx. 

History
In the 23rd century, Kukulkan captured one as a cub and kept it in his shipboard zoo. Its environment was simulated holographically. 

In 2267, the booming voice of Grigoriy Nemov reminded Aneher II's Daniel Latham of a maddened power-cat. 

In 2269, a landing party from the USS Enterprise (NCC-1701) freed Kukulkan's captured power-cat, allowing it to wreck havoc in the zoo while they escape. James T. Kirk then injected it with a hypo, getting jolted in the process, in order to tranquilize the animal.