Bed bug

Primarily indoors, hiding in mattress seams, bed frames, upholstery, cracks, and other sheltered crevices near sleeping hosts.

Feeds exclusively on blood, mainly from humans but also other warm-blooded animals. It typically feeds at night using piercing-sucking mouthparts.

Wingless, nocturnal, and attracted to body heat and carbon dioxide; adults and nymphs can survive for months without feeding. Females lay eggs in protected cracks, and infestations spread by hitchhiking in luggage, clothing, and furniture.

Bites cause itchy welts and occasional allergic reactions, but bed bugs are not established vectors of disease. They provide little ecological benefit indoors and are difficult to eliminate without thorough treatment.