[Photo] Engorged female Cimex lectularius, the human bed bug

Bedbugs (or bed bugs) are small nocturnal insects of the family Cimicidae that live by hematophagy, that is by feeding on the blood of humans and other warm-blooded hosts.

The common bedbug (Cimex lectularius) is the best adapted to human environments. It is found in temperate climates throughout the world and has been known since ancient times.