Bed bug

Beds, upholstered furniture, luggage, cracks, and other sheltered indoor locations, especially near sleeping hosts.

Feeds almost exclusively on blood, mainly from humans but sometimes other mammals and birds.

Nocturnal and attracted to warmth and exhaled carbon dioxide; hides by day and can survive for months without feeding. Females lay eggs in protected crevices, and infestations spread through transported belongings.

Bites cause itchy welts and occasional allergic reactions, but bed bugs are not known to transmit disease routinely. They provide little meaningful ecological benefit indoors.