The Kryonian tiger was a large, threatening predator that was endangered by the late 24th century.

In 2368, Alexander Rozhenko and Worf saw a Kryonian tiger on the protected planet of Brentalia. Alexander did not find the tiger particularly scary after it licked his hand, and he remarked that it "smelled funny". (TNG: "Imaginary Friend")

Star Trek: The Starfleet Survival Guide describes the Kryonian tiger as a large cat that lives in arctic environments.
The Decipher RPG book Creatures describes the Kryonian tiger as a simian that lives in the forests and jungles of Kryon V.