Hide and Larder Beetles

HYG-2104-95

Common Name	Scientific Name
Larder Beetle	Dermestes lardarius Linnaeus
Hide or Leather Beetle	Dermestes maculatus (DeGeer)
Black Larder or Incinerator Beetle	Dermestes ater (DeGeer)

Hide and larder beetles infest a wide variety of substances, especially those of animal origin. Both adults and larvae feed on cured meats, dried fish, cheeses, raw skins, hides, furs, feathers, hair, fish meal, dry dog and cat food, stored tobacco, stuffed animals, dead insects in wall voids, museum specimens, abandoned bird nests, dead rodents in wall partitions or chimneys, dead beehives, and even rat or mouse poison baits. Infestations are often hard to locate because beetles and larvae can migrate far from the original food source.

Identification

Adult larder beetles are about 1/3 inch long and dark brown, with a broad, pale yellow, black-spotted band across the front portion of the wing covers. There are six black dots on this band, three on each wing cover, arranged in a triangle. The underside and legs are covered with fine, yellowish hairs. The hide or leather beetle is similar in shape to the larder beetle except the wing covers are entirely dark and the body underside is mostly white. Black larder or incinerator beetles are dark with scattered yellow hairs on the body. All larvae are longer than adult beetles (up to 1/2 inch), slender, densely covered with short and long hairs and reddish-brown to black, with two spines on top near the tail end. Larder beetle larvae spines curve backward, hide or leather beetle larvae spines curve forward, and black larder or incinerator beetle larvae spines extend backward and are not strongly curved.

Larder Beetle, adult, larva, enlarged spike

Life Cycle and Habits

Adult larder beetles usually overwinter outdoors in protected places. They occasionally are found outdoors on flowers feeding on pollen. During the spring and early summer, they enter buildings, with females laying eggs near a food source. Females each lay about 135 eggs, which hatch in 12 or more days. Larvae prefer spoiled ham, bacon, dried beef and other meats. Larvae either bore into this meat or wander away to bore into wood, books and even metals such as lead and telephone cables to pupate. The life cycle requires 40 to 50 days. Adult hide or leather beetles and larvae prefer to feed on raw skins and hides. Females may each lay up to 800 eggs. The life cycle is completed in 60 to 70 days. These larvae have a habit of boring into wood and other hard materials to pupate. Sometimes structural timbers may be damaged.

Adult black or incinerator beetles often infest pet foods and waste materials burned in incinerators. Most beetles are strong fliers, are attracted to lights and may invade structures through various openings. Cultures are often considered useful and are kept to permit larvae to clean the flesh from skeletons for museum purposes.

Poultry Houses

Mature larvae of hide beetles have the habit of boring into various hard surfaces to pupate, usually preferring softwoods. Some may climb 24 to 36 feet and bore into posts, studs and rafters seriously weakening and "honeycombing" these structures. Larvae are especially troublesome in poultry houses, damaging yellow pine, foam insulation, styrofoam air baffle boards and even PCP (Penta Ready) chemically treated wood in some cases. Larvae emerge from the litter, climb the walls and bore into soft building material, often escaping cannibalism during the pupation period. Reasonable control has been achieved by applying tetrachlorvinphos (Rabon 50) WP in the dry form to the building walls. Make treatments with an electrostatic duster so as to negatively charge the particles, providing better adhesion to the wall surface. A distributor for the duster (model DM-9) is Echo Inc., 3150 MacArthur Blvd., Northbrook, Illinois 60062. Also, labeled for pest control operators and commercial applicators is cyfluthrin (Tempo) as a spray to litter, walls and center posts inside the poultry house. A new insecticide labelled for control of darkling beetles, hide beetles and flies, known as orthoboric acid (SafeCide), provides long residual control up to nine to twelve months or longer. Both adult beetles and larvae are killed by contact or ingestion.

Control Measures

Prevention

Modern methods of commercial slaughtering, meat storage and meat distribution have reduced potential infestations of hide beetles. Occasionally, home-cured meats and raw skins or hides become infested. The presence of this insect in the home may indicate a dead rodent between the walls, in the crawlspace or the chimney. Be sure to eliminate bird nests, clean light globes of dead insects, remove dead rodents from traps, check dry dog and cat food stored for long periods of time, and caulk all openings where beetles might enter when attracted to lights. Flies such as the cluster fly and face fly, abundant in the autumn, hibernate in home wall voids, attics, overhangs, etc. Many die in inaccessible places and become a prime food source for larder beetles. Store susceptible foods in insect-proof containers of glass, aluminum or steel, ideally with screw-type lids, or store in a refrigerator. Larvae have been known to bore through lead and tin materials for pupation. Routinely inspect stuffed animals and even old wax combs where honey bees have died out. These beetles will infest museum collections of insects, animals, etc., if not properly preserved. One can kill these insects in foods by heating in a shallow pan in the oven at 130 to 135 degrees F for three hours, placing in a deep freeze at 0 degrees F for seven days, or placing in a microwave oven for three to five minutes or longer, depending on the size of the food package. Killing these insects in infested foods will prevent them from spreading. Vacuum individual beetles and spilled foods, dust and dirt around baseboards. Discard sweeper bag contents far from the house after spraying or killing. Dispose of heavily infested foods in heavy plastic bags placed in tight-fitting garbage cans, or bury deep in the soil.

Insecticide

As it is often difficult to locate the source of infestation due to the migration habits of these insects, spot treat only to crack and crevice sites where they are suspected of hiding. Larvae often appear scattered throughout a building far from the original food source. They may be in a wall void or attic where dead insects (flies) or rodents provide a food source. Pyrethrins are labeled for hide beetles. Many insecticides labeled for carpet beetles will give control. Only the licensed pest control operator or applicator can apply fumigants. Before using any insecticide, read the label, follow directions and safety precautions.

This publication contains pesticide recommendations that are subject to change at any time. These recommendations are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. Due to constantly changing labels and product registration, some of the recommendations given in this writing may no longer be legal by the time you read them. If any information in these recommendations disagrees with the label, the recommendation must be disregarded. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned. The author, The Ohio State University and Ohio State University Extension assume no liability resulting from the use of these recommendations.