Assassin Bug, common name for a long-legged predatory insect that stalks other insects. They are found throughout the world with over 135 recognized species in North America. Most species of assassin bugs are considered beneficial because they help control insect pests.
The adult assassin bug is relatively large, usually 11 to 37 mm (0.5 to 1.5 in) in length. As with most true bugs, it has thickened forewings with membranous tips for handling prey. When at rest, the extended, segmented beak can be folded back underneath its body. Its folded wings overlap, giving the back a characteristic shape. Adults are commonly black, reddish, or brown, with long, slender legs, a narrow head, and round, beady eyes. Some species have sharp barbs on their forelegs to prevent prey from escaping.
All assassin bug species are predatory, primarily feeding on caterpillars and other insects. The assassin bug uses its needlelike beak to impale prey. It then injects a venom that both paralyzes and partially digests the prey. The body contents of the victim liquefy and are sucked out with the assassin bug's strawlike mouth parts. A few species, like the western bloodsucking conenose, commonly bite humans and other mammals. These bloodsucking species are sometimes called kissing bugs because they are attracted to exposed tender flesh, such as the face and lips of sleeping humans. Even species that prey only on insects can inflict painful bites on humans with inflammations that can persist for several days.