Pest Briefs: Beetles 101
By: Robert (Bob) Batman

NATURAL ENTOMOLOGICAL CLASSIFICATION

Phylum Arthropoda
Class Hexapoda or Insecta
Order Coleoptera
Family Various (see below listed)
Genus/species Various

Morphosis: Complete (egg, larva, pupa, adult)

Beetles are insects. There are a variety of beetles (including weevils) that are common household pests(does not include lawn, shrub, tree, field crop, or garden pests). One usually discusses pests under groupings such as wood-destroying insects, stored products pests, fabric pests, flying insect pests, or etc., and most of the more common groupings includes beetles plus other insect and insect-like pests. There are valid reasons for revisiting the study of household pests from an approach other then the standard. To some extent this pest brief strays from the norm: it covers only the beetles which are common household pests.

BEETLES ARE IMPORTANT TOO! The Order Coleoptera (beetles and weevils) is the largest of all the Orders of insects: approximately two out of every five known insects are beetles. In 1962, when I was studying insect classification and insect morphology in college, there were 24 different families of beetles in the Order Coleoptera. Each family consisted of numerous genera and species. Out of the 24 families only 12 families contained a species which was considered to be a common household pest. The 12 families are listed below along with the common name(s) of the specific pest species. Obviously, this brief is not all inclusive. However, it does point out that silverfish, clothing moths, various meal and grain moths, carpenter ants, and termites (none of which are beetles) are not the only pests out there.

BEETLES CAN CAUSE DAMAGE! In many cases it is the larva stage of the beetle which causes the damage, however, in some cases the adult is the pest. The term beetle as used herein refers to whatever stage (larva or adult) of the insect that causes damage and/or by infesting or invading becomes a nuisance. These household pest beetles can be divided into the following four (4) categories:

1. Wood-Boring (structural), Book-Boring and Related Beetles
2. Fabric, Carpet, and Hide Beetles
3. Beetles That Infest Stored Food Products
4. Occasional Beetle Invaders

WOOD-BORING BEETLES: This brief is limited to the beetles listed in the following five (5) Families of wood-boring beetles: 1) Family Buprestidea (the metallic beetles, sometimes referred to as flathead bores), 2) Family Lyctidea (the true powder post beetles), 3) Family Anobiidea (deathwatch and furniture beetles), 4) Family Cerambycidae (the long-horned beetles; old house bores, new house borers, and etc.) and, 5) Family Scolytidea (bark and ambrosia beetles). These beetles, adults and/or larva, feed on wood, paper and cardboard items. They can cause extensive damage. As you can see, termites and carpenter ants, neither of which are beetles, are not the only wood-destroying insects.

POINT OF INFORMATION: A termite inspection is limited to inspecting readily accessible areas for visible evidence of termite infestation. A termite is only one of several wood-destroying insects! If you are buying a house, perhaps you should consider requesting a wood-destroying insect (WDI) inspection instead of a termite inspection: it includes all the wood-destroying insects, not just termites! FHA and VA loans require a WDI, and the inspector must use the NPCA-1 inspection report form for said inspections. This form is also approved for other type (conventional, etc.) real estate transactions.

FABRIC, CARPET, and HIDE BEETLES: Basically, various species ( and there are several) of the Family Dermestidea (carpet beetles, larder beetles, warehouse beetles, lesser museum beetles, larger cabinet beetles, and the odd beetles) cause fabric, carpet and/or hide damage. Some of these pests are very common, and some are also pests of stored and dried food products. The larva of these pests can cause serious damage! I've seen large numbers of carpet beetle adults on spirea bushes and other plants, and many of the infested bushes were against the exterior siding of houses. The tiny carpet beetle adults would have no problem gaining access into the houses. The adults of these pests are nectar and pollen feeders, the larva can cause damage to fabrics, carpeting and hides.

ACTUAL CASE SITUATION: I can't even count the times a potential customer holds up an article of clothing and says, "look what the silverfish have done." This happened to me just last week! I looked at the subject garment and knew instantly the damage was not caused by silverfish. The visible damage was typical of that caused by carpet beetle larva, and cast off carpet beetle larval skins were present under the collar of the garment. Additional cast off larval skins were found, by me, within the closet where the garment had been stored. I told the potential customer that she may very well have a silverfish problem, but clothing damage was caused by carpet beetles. After my brief explanation to the potential customer, she authorized appropriate service. Silverfish infestation is a major pest problem in our part of the country, but silverfish are certainly not the only fabric pest.

Silverfish infestation demands appropriate and timely control aids, but they are not the only bug in town! See our Pest Brief on Silverfish, but don't forget the moths and the beetles! Also, see our Pest Brief on Fabric Pests: it includes all the fabric pests, including the beetles.

BEETLES THAT INFEST STORED FOOD PRODUCT: Following are five (5) families of the Order Coleoptera that have members which infest stored food products. 1) Family Dermestidea (carpet and hide beetles): also see above, 2) Family Cucujidae (flat, bark and grain beetles), 3) Family Trogositidae (bark and gnawing beetles; includes the cadelle beetle), 4) Family Tenebrionidae (darkling beetles; includes meal worms, the red flour beetle and the confused flour beetle) and, 5) Family Curculionidae (weevils and snout beetles). These beetles, and other pests (other than beetles) contaminate and damage stored food products. Generally the beetles (eggs, larva, pupa, and/or adults) are in the food product before it is purchased by the consumer. Evidently the beetles cannot read the shelf codes on the product containers, and neither can anyone else that hasn't taken a six-month code braking course at Langley. I've seen beetle infestation (the pests emerging from inside food and food containers) in product on retail store shelves long before the product's shelf code expiration date. The life cycle (from egg to egg laying adult) of some of these beetles is as short as 60 days at normal inside temperatures, but the shelf life code of some of the products they infest is as long as one year. In addition to these pests causing consumers problems, they are nemesis of farmers and pose continual problems for the managers of commercial processing, storage, distribution, and retail service facilities. Both adult and larva forms are considered pests and contaminators or stored food products. Some of these beetles (one life stage or another) are commonly found infesting dried flower arrangements, wool carpeting, wool clothing, fur coats, and stuffed-mounted animals, to name a few things.

OCCASIONAL BEETLE INVADERS: Occasionally some bugs, in this case adult beetles, wander into a building from outside. These are referred to as occasional invaders. Actually any bug that wanders into a building from outside could, in one sense or another, be considered an occasional invader. For the purpose of this brief, we shall consider as occasional invaders only those beetles which are not otherwise considered common household pests. The beetles listed by common name in the following families of Coleoptera are considered occasional invaders: 1) Family Chrysomelidae (leaf beetles), 2) Family Carabidae (ground beetles) and, 3) Family Coccinellidae (lady beetles). These are a few of the beetles that may come into your bedroll, foxhole, cave, tent, house, or office to visit or, perhaps, to simply get out of existing weather conditions. They either like it inside, and stay, or they simply cannot find their way back out. Usually it is the adult form you encounter invading the inner sanctums of your bedroll or abode. Please don't call me and complain that these beetles are not occasional invaders because you find them in your house or office all the time. I didn't write the book on occasional invaders and their capabilities: I'm just a lowly messenger.

NOTE: This PEST BRIEF on BEETLES has been limited to beetles that damage wood, fabric and carpet or hides, stored food products, and some that are considered occasional invaders.

If you live in the Greater Kansas City (Missouri and Kansas) Metropolitan Area, call Best at (816) 765-8844 weekdays between 8:00 AM and 4:30 PM. Best Exterminators, Inc. Main Office Number: (816) 765-8844.