Painful-bite
Guides
Arilus cristatus
North American wheel bug, wheel bug
Arilus cristatus, the North American wheel bug, is a large assassin bug distinguished by a semicircular, wheel-shaped pronotal crest. Adults reach up to 38 mm in length and are gray to brownish-gray, while nymphs are bright red and black without the characteristic wheel structure. The species is a generalist predator that employs raptorial front legs and a powerful proboscis to subdue and liquefy prey. It is valued as a biological control agent but possesses a defensive bite to humans that is notably painful and prolonged.
Corydalus texanus
Western Dobsonfly
Corydalus texanus is a large megaloopteran insect commonly known as the Western Dobsonfly. Adults are among the largest winged insects in their range, with males distinguished by elongated sickle-shaped mandibles used in combat with rivals. Females possess shorter but powerful jaws capable of delivering a painful bite. The aquatic larval stage, known as hellgrammites, are predaceous and serve as important indicators of stream health. Adults are attracted to lights and may be observed near water bodies at night.
Hesperocorixa vulgaris
water boatman
Hesperocorixa vulgaris is a species of water boatman in the family Corixidae, first described by Hungerford in 1925. This aquatic true bug is found in North America and is most active during spring through autumn. It feeds primarily on algae, which it sometimes stirs up from waterbeds. When threatened, it can deliver a painful bite.
Lethocerus
giant water bugs, toe biters, electric light bugs
Lethocerus is a genus of large predatory aquatic true bugs in the family Belostomatidae. Members are among the largest true bugs, with some species exceeding 12 cm in length. The genus is distinguished from related genera by specific morphological features of the fore femur and parasternites. Unlike other giant water bugs, females do not deposit eggs on males' backs; instead, eggs are laid on emergent vegetation above the waterline and guarded by males. The genus shows greatest diversity in the Americas, with limited representation in Europe, Africa, Australia, and Asia.
Melanolestes picipes
Black Corsair, Black May Beetle-Eater
Melanolestes picipes, commonly called the Black Corsair, is a predatory assassin bug in the family Reduviidae. The species exhibits pronounced sexual dimorphism: males are fully winged and strong fliers, while females typically have reduced or absent hind wings and merely pad-like forewings. Adults measure 15–20 mm in body length. Northern populations are uniformly jet black; southern specimens may display red or orange abdominal margins or entirely red abdomens. The species is among the most abundant assassin bugs in the United States and is frequently attracted to outdoor lights at night.
Rasahus thoracicus
Western Corsair Bug, Western Corsair
Rasahus thoracicus, commonly known as the Western Corsair Bug, is an assassin bug in the family Reduviidae. Adults display orange and black coloration with distinctive orange spots on each wing. The species is nocturnal and attracted to bright lights, where it hunts other insects. Unlike most assassin bugs, its bite is notably painful to humans. It is one of two "two spotted corsairs," the other being Rasahus biguttatus.
Reduvius personatus
Masked Hunter
Reduvius personatus, commonly known as the masked hunter, is a cosmopolitan assassin bug recognized for the distinctive debris-camouflaged appearance of its nymphs. The species is a generalist predator of small arthropods and has been introduced to multiple continents through human activity. Adults are uniformly dark brown to black, winged insects measuring 17–22 mm, while nymphs appear gray or light-colored due to accumulated dust and lint on their bodies. Though beneficial as predators of household pests like bed bugs, they can deliver a painful defensive bite when mishandled.
Tabanus
True Horse Flies, Horse Flies
Tabanus is a large genus of biting horse flies in the family Tabanidae, containing hundreds of species distributed worldwide. Females possess scissor-like mouthparts adapted for cutting skin to access blood meals from mammals, including livestock and humans. The genus includes some of the largest horse flies in North America, with species such as Tabanus americanus reaching up to 30 mm in body length. Members of this genus are significant from a veterinary and medical perspective as potential vectors of pathogens including anthrax, worms, and trypanosomes.