Highlight Of Bed Bugs And Their Relatives

The common human bed bugs (Cimex lectularius L.) are bloodsucking insects of the family Cimicidae. This family includes the common human bed bugs (C. lectularius), tropical bed bugs (C. hemipterus (F.)), bat bugs (C. adjunctus Barber), swallow bugs (Oeciacus vicarious), Mexican chicken bug (Haematosiphon inodorus), and other insects with no reported common names (Usinger, 1966). Henry and Froeschner (1988) have reported that there are 92 species of Cimicidae in the world and about 16 species in the continental U.S. and Canada.

Due to the sudden, overwhelming and obnoxious resurgence of the common bed bug in all kinds of residences, schools, medical centers, theaters, and retail stores, a great attention has been given to these troublesome pests in literature and media. Anyhow, little is known about bed bug relatives, because they are less frequently encountered in buildings. Additionally, they have never been proven that they can transmit any infectious pathogenic organisms to humans and pets. But, a few bed bug related species might also be exceedingly encountered in or around buildings; thus, inexperienced individuals may mistake them for the bed bugs. This will eventually lead to a treatment failure.

Since a successful remediation plan always starts with a proper identification of the pest, I would like to shed some light on a few Cimicidae species, which may have a special importance to the pest management professional. First, there are common features that all Cimicidae have. All Cimicidae species cannot jump or fly, but they can move and spread by crawling or hitchhiking. They are temporary, obligatory hematophagous ectoparasites, meaning that they are external blood feeders and do not live on their hosts. Besides, they have piercing and sucking mouthparts that they use to obtain blood meals from warm-blooded creatures, such as humans, birds, bats, dogs, cats, etc. During feeding, they inject anesthetic and anticoagulant substances responsible for leaving the host unaware of their presence and preventing blood from clotting. When they are fully engorged with blood, they hide in cracks, crevices and folded places near hosts between meals.

As aforementioned, a correct identification of bed bugs and their related species is critical for finding the proper treatment option. In this article, I will be discussing identification features of common bed bugs and four other related species. 

Common Bed Bugs

The common bed bug is about 3/16-1/4-inch-long, oval and reddish-brown in color. Nymphs are nearly colorless when hatched, becoming brownish as they mature. Females lay white, sticky, pear-shaped, approximately 1/32-inch long eggs in concealed areas, such as any crack, crevice or void in mattresses, box springs, furniture, wall, ceiling, behind baseboards, etc. With no trouble, they can get a ride on luggage, clothing, beds, furniture, or other items, and relocate to a new home. They are nocturnal, but still, they can feed and be seen during the day, especially in heavily infested areas.

Bed bugs are resilient pests. They can hide in tough places around people’s sleeping areas and can easily spread from one area to another on clothing or through common walls, ceilings and entry doors. Additionally, they have developed a resistance to pyrethroid insecticides (a group of pesticides commonly used in the structural pest control industry). Therefore, eliminating of all bed bug life stages, including eggs (the most resilient stage) can sometimes be a challenge in certain places. They may require the implement of both non-chemical pest management tactics, such as heat treatment and the use of chemical control methods. If chemical control option is needed, all bed bug hiding places must be carefully identified by your Pest Management Professional (PMP) and treated. The use of various approved liquid treatments on surfaces and dusts in void areas should be thoroughly and carefully implemented.

Tropical Bed Bugs

Tropical bed bugs also are associated with humans in tropical regions. To the naked eye, common and tropical bed bugs may look nearly identical. But under magnification, the key feature to differentiate the two species is that the pronotum (the upper surface of the front segment of the thorax of an insect) of the common bed bug is more expanded laterally and the extreme margins are more flattened than that of the tropical bed bug. The width of pronotum is two times the length at midline.

Bat Bugs

Bat bugs and bed bugs look identical to the naked eye. However, under a stereoscope (magnification between 20x and 50x), one distinguishing feature is that the fringe hairs on the pronotum (the upper covering of the thorax) of the bat bug are as long or longer than the width of the eye, but are shorter in the bed bug. The primary hosts of bat bugs are a variety of bat species, especially the big and little brown bats, which roost in colonies, but they can feed on warm-blooded animals, including humans in the absence of bats. Bat bugs are often encountered inside a structure when bats are established in attics, wall voids, unused chimneys, or any uninhabited places of the building. Typically, bat bugs are found in cracks and crevices in bat roosting areas. But, if the primary hosts (bats) leave the nesting area, die or are eliminated, bat bugs start moving inside a structure within 1-4 weeks to feed on alternative hosts. These include birds, rodents, and humans. Once in the structure and having found a host on which to live, bat bugs will become established the same way as bed bugs. Additionally, they will spread the same way as bed bugs.

To control bat bugs, bats must be excluded from access into the buildings and nests must be removed. Once the external source of bat and bird bugs has been removed, control inside the building is the same as for bed bugs.
However, the frequency of bat bug infestations in structures is very low as opposed to bed bug infestations.

Swallow Bugs

Swallow bugs feed primarily on cliff swallows (Petrochelidon pyrrhonotaVieillot). These birds nest in colonies and their nests can be occupied year round by swallow bugs. They are about 1/8 inch long. The defining characteristics of swallow bugs include their middle coxae (singular coax; the first segment of the leg of an insect or other arthropod, joining the leg to the body), which are wildly spread, the beak does not reach the second coax, as well as the third and fourth antennal segments are equal in length. Like bat bugs, swallow bugs may feed on humans and their pets as suitable alternatives when they nest around buildings and the host birds migrate or the nesting site becomes overpopulated. They also can move to other nests while attached to a host. Similar to bed bugs, they do not lash on their host and will fall off during a long migration flight.

Treatment of swallow bugs is similar to that for bat bugs.

Mexican Chicken Bug

Mexican chicken bug, (sometimes called poultry bug) is a bloodsucking ectoparasite of a various species of birds, such as chickens, turkeys, golden eagles, red-tailed hawk, etc. The major characteristic to separate the Mexican chicken bug from other cimicidae species is that the middle coxae are nearly touching and the beak is reaching the second coax. Although this species is found in cracks and crevices in poultry houses, it is relatively uncommon inside homes where people live, unless occasionally in special situations when their primary hosts are removed or when humans get in touch with them as they try to protect the birds from these bugs.

Treatment of Mexican chicken bugs is similar to that for bat bugs.

In conclusion, before treatment, make sure that the bug is correctly identified. Manage to collect the bug specimen intact, and have a specialist correctly identify it. This will save time, effort and money. As we always say, it all starts with the bug. Be aware that bed bugs are resilient pests, for this reason, their management may require the utilization of both non-chemical (i.e., heat treatment) and chemical pest management tactics.

Henry TJ, Froeschner RC (eds.). 1988. Catalog of the Heteroptera, or True Bugs, of Canada and the Continental United States. E. J. Brill, New York. 958 p.

Usinger, R. L. 1966. Monograph of Cimicidae (Hemiptera: Heteroptera). College Park, Maryland: Entomological Society of America. i-xi, 1-585 p.