Ohio State University Extension Factsheet

Ohio State University Extension Fact Sheet


1991 Kenny Road, Columbus, Ohio 43210-1000

Assassin Bugs


William F. Lyon
Common Name Scientific Name
Bloodsucking Conenose Triatoma sanguisuga (LeConte)
Masked Hunter Reduvius personatus (Linnaeus)
Black Corsair Melanolestes picipes (Herrich-Schaeffer)
Wheel Bug Arilus cristatus (Linnaeus)
Spined Assassin Bug Sinea diadema (Fabricius)

Assassin bugs, sometimes known as conenoses or "kissing bugs," are occasionally found in the home (bathtubs, sinks, drains, etc.) and, if handled carelessly, can inflict a very painful bite, causing a severe reaction in some persons. Some are attracted to lights and require blood meals to complete their development. Many are bloodsucking parasites of mammals, including humans. Others are predators, feeding on bed bugs, flies, caterpillars and other insects. Most are found in late June to early August. These bugs have a long narrow head, short beak (three-segmented), long slender antennae (four-segmented) and an abdomen often widened at the middle exposing the margins of the segments beyond the wings. Occasionally, they are confused with the leaffooted bug which is distinguished by its flattened (leaf-like) hind legs.

Identification, Biology and Behavior

Bloodsucking Conenose

Adults are 3/4 to 13/16 inch long, brownish-black, broad, stout-bodied with six reddish orange spots on each side of the abdomen, above and below. Eyes are large with an elongate protruding head. The beak is not curved (slender and tapered) and almost bare. It is kept folded back between the front legs when not used. Adults are winged and able to fly. They are found in nests of rats and will feed on any animal including humans. Oval, pearly-white eggs are laid singly from May to September. Each batch is laid after a blood meal. Nymphs have eight instars requiring three years for the life cycle.

The conenose is a vector of Chagas disease prevalent in Mexico, Central America, and South America, where these bugs may colonize human habitations. This sometimes fatal disease, caused by a flagellate protozoan, has symptoms of swelling of the eyelids and face, loss of nervous control, high fever, anemia and destruction of the cardiac and skeletal muscles. This disease is not common in the United States.

The bloodsucking bugs are active at night usually feeding on sleeping victims. These bugs are usually found outdoors in hollow trees, in raccoon and opossum dens, or near wood rat nests. Indoors, they are found in bedding, floor and wall cracks, under furniture, etc. They are poor fliers and sometimes attracted to lights. Bites are sometimes painless, but may cause a severe reaction. They are more often a problem to people living in wooded areas.

Masked Hunter

Adults are 3/4 to 7/8 inch long, chocolate brown, beak curved (not slender and tapered), with slender antennae and walking-type legs. They are called "kissing bugs" and are attracted to lights. They are very active and enter houses in search of bed bugs, flies, and other insects. Eggs are laid singly in the dust in cracks and corners. Nymphs have the body, legs, and antennae covered with a sticky substance to which dust and lint adhere especially on the head (thus, the name, masked) and are only visible when moving. Nymphs hibernate in the 4th to 5th instar and reach maturity the following spring. Bites are very painful on humans.

Black Corsair

Adults are black and 9/16 to 11/16 inch long. They resemble the masked hunter except have short wings. Adults overwinter under stones and are collected in early spring. Bites are painful to humans.

Wheel Bug

Adults are 1-1/4 inch long and have a slender, long antennae (reddish-brown). The body is grayish-black with an upright one-half "cogwheel-like" crest on the thorax bearing 8 to 12 protruding teeth-like structures. The membrane of the front wing is coppery colored. Wheel bugs are rather uncommon, but attract attention when found due to their bizarre appearance. They are voracious predators, attacking large caterpillars, such as tomato hornworms, and suck them dry. They will not bite humans readily, but when they do, the bite is very painful.

Spined Assassin Bug

Adults are 1/2 to 9/16 inch long, brown colored, narrow, angular, and rough-bodied. The head, thorax (middle part) and front leg (upper portion) are covered with spines and the female's abdomen is wavy. Cylindrical white eggs are laid in small groups covered with a reddish secretion. These bugs are very beneficial to agriculture, feeding on many injurious insects, attacking all stages of the Mexican bean beetle.

First Aid

Bites may be hardly felt by the bloodsucking conenose in contrast to painful bites by the masked hunter, black corsair, and wheel bug. Sensitive individuals may experience burning pain, intense itching and much swelling with red blotches and welts over the body. If bitten, remain calm and safely collect the bug for positive identification. Do not handle bugs without gloves. Contact your local poison information center to seek medical help. Relief from bites may be obtained by using lotions containing menthol, phenol or camphor.

Control Measures


All potential breeding areas such as rodent and bird nests and trash piles in or near houses should be eliminated. Since these bugs fly at night and are attracted to light, adequate screening must be used around windows and doors. Use non-attractive insect yellow lights, if possible. Be sure to caulk and seal any openings into the house. Should a bug alight on one's face or hand, it should be brushed off gently since it is likely to bite if pinched or crushed. Usually only a few individual bugs are found in the home at one time except for the bloodsucking conenose, which may be in groups of 10 to 15 at a time or scattered singly. Do not handle bugs. Use a broom and dustpan or vacuum cleaner to collect and discard individuals.


A household aerosol spray of pyrethrins can give good knockdown and kill against individuals. These bugs can be controlled with a spot treatment of a residual household crawling insect spray such as diazinon or propoxur (Baygon). Pyrethroid insecticides such as permethrin is the most effective at high concentrations. Before using any insecticide, always read the label, follow directions and safety precautions.

All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.

Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.

TDD No. 800-589-8292 (Ohio only) or 614-292-6181

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