Bed bug (Cimex lectularius), coloured scanning electron micrograph (SEM). Bed bugs (family Cimcidae) are wingless, parasitic insects. They grasp human skin with their forelegs, pierce the skin, and inject anticoagulant and an anaesthetic containing saliva. They feed at night. The female lays approximately 300 eggs. They don't transmit diseases but can cause skin infections from scratching bites. Magnification: x27, when printed 10cm wide.