Bed bug

Human dwellings, particularly in and around beds, mattresses, bed frames, seams, furniture cracks, and baseboards.

Hematophagous (obligate blood-feeders), primarily feeding on human blood, though they may also feed on other warm-blooded animals.

Nocturnal and secretive; they hide in narrow crevices during the day and emerge at night attracted by heat and carbon dioxide to feed. They reproduce rapidly via traumatic insemination and can survive months without a blood meal.

Risks include itchy red bites, allergic reactions, secondary skin infections from scratching, sleep deprivation, and significant anxiety or psychological distress. They are major domestic pests; they offer no ecological benefits in human environments.