Adder

Adders are snake critters that can be found in many areas of Azeroth and Outland. They're especially abundant in arid places, such as Durotar and Hellfire Peninsula.

Pet Journal
Unlike other snakes that actively hunt, these crafty reptiles hide in thick foliage and ambush their prey.

Criteria of
Killing one of these is required for Pest Control while also capturing one is required for the following:
 * Eastern Kingdoms Safari
 * Kalimdor Safari
 * Outland Safari