From the publishers homepage:
Beware the Beasts
The Awakening had a dramatic effect on the world, and those effects have not stopped shaking things up. Across the Sixth World, magic and other environmental factors continue to twist and distort all variety of living things, and the results can be deadly - or useful, to those who know how to harness the powers let loose in the animal kingdom.
Parazoology brings several critters from earlier editions of Shadowrun into Fourth Edition, while also introducing brand-new beasts. Inside you’ll find the stealthy and predatory cactus cat, the mind-altering stone toad, the horrific sea wolf, and twenty-seven other critters. Complete with full-color illustrations and game statistics for every beast, Parazoology provides a host of challenges, dangers, and potential resources for your Shadowrun game.
Parazoology is for use with Shadowrun, Twentieth Anniversary Edition.