Close Up Of Praying Mantis - Mantises are exclusively predatory and their diet usually consists of living insects; larger species have been known to prey on small lizards, frogs, birds, snakes, and even rodents. Most mantises are ambush predators, waiting for prey to stray too near. The mantis then lashes out at remarkable speed. Some ground and bark species, however, pursue their prey rather quickly. Prey are caught and held securely with grasping, spiked forelegs ('raptorial legs'); the first thoracic segment, the prothorax, is commonly elongated and flexibly articulated, allowing for greater range of movement of the front limbs while the remainder of the body remains more or less immobile.