F@stSheet Ent-1045

Hide and Larder Beetles IN THIS F@STSHEET IDENTIFICATION DAMAGE BIOLOGY CONTROL FOR MORE INFORMATION

Hide and larder beetles are occasional pests of households where they feed on a wide variety of animal protein-based products. Common foods for these beetles include leather goods, hides, skins, dried fish, pet-food, bacon, cheese, and feathers.

Three of the most common species, the hide, larder, and black larder beetles are known scientifically as Dermestes maculatus, Dermestes lardarius, and Dermestes ater.   All three belong to the insect family called Dermestidae, and are related to carpet beetles, a more common group of indoor insect pests.  Many Dermestes beetles are cosmopolitan, meaning they are distributed around the world. The hide and larder beetles are thought to have originated in Eurasia; while the black larder beetle is believed to be indigineous to North America.

IDENTIFICATION
Adult Dermestes beetles are relatively large, ¼ - 3/8 inches-long, and dark brown to black with various markings (right Figure above). Sides of the body are subparallel, convex, shiny, with moderate pubescense (no scales). Median eye-spot (ocellus) absent. Grooves (striae) on wing covers (elytra) are indistinct.

The hide beetle is white on the underside with two white or yellowish patches on the lateral third (and sometimes the anterior edge) of the dorsal surface of the pronotum. The hide beetle's coloration, together with the acutely pointed and saw-like (serrated) tips of the elytra, serve to separate it from other Dermestes species. The larder beetle is easily distinguished by a distinct cream-colored band across the top third of the elytra, sometimes with three small black patches on each side. The black larder beetle is distinguished from the similar hide beetle by the lack of a pointed elytral tips, and by the presence of small patches of white hairs (setae) on the underside of the third and fourth abdominal segments of the male (females have no patches), compared to patches on only the fourth segment of hide beetle males.

Dermestes larvae are heavily to completely covered with setae (hairs), giving a fuzzy appearance (Figure A). Dermestes larvae are generally dark brown to black and possess a pair of large, curved, conspicous "horns" (urogomphi) on the terminal segment of the abdomen.

Adult Dermestes can be distinguished from other dermestid beetles by their relatively large size and lack of a median eye-spot on the head (a character that requires magnification to see). Larval Dermestes are distinguished by the presence of urogomphi on the last abdominal segment.

DAMAGE
Dermestes beetles feed on a wide variety of animal protein-based products and are serious pests in silkworm production and in museums. Common food sources include leather goods, hides, skins, dried fish, pet-food, bacon, cheese, and feathers. Household infestations are sometimes attributed to the presence of bird or rodent carcasses, old bee nests, or accumulations of dead insects. Dermestes may possibly feed on plant material of high protein content, but this is not a preferred food source. Hinton (1945) suggests that when the larder beetle is present in granaries and warehouses containing cacao, dried fruit, etc., it is probably feeding on the bodies and exuviae of other insects. Mature Dermestes larvae also bore into hard substrates such as wood, cork, tobacco, plaster, etc. to pupate. The hide beetle is sometimes used by museums for cleaning bones and skulls.

BIOLOGY
Females require a continuous supply of water and food to acheive their maximum egg-laying capacities. Female hide beetles provided with dried meat and water lay an average of 318 eggs. Eggs are laid singly or in small batches on the food source, and hatch within 4 to 6 days. Numbers of instars vary, depending on the temperature and quality of the food source. Optimum temperatures for development are between 64 to 68 degrees F. At 75% RH and 70 degrees F, on a diet of dried meat, the hide beetle passes through 7 to 9 molts and completes its larval development in an average of 50 days. Under these temperature and humidity conditions, the pupal stage lasts 20 to 22 days and adult hide beetles live 169 to 173 days.

CONTROL
Locating and eliminating sources of infestations, as well as good preventive sanitation, are keys to control of Dermestes infestations. Cold storage at temperatures less than 50 degrees F is an effective method for protecting furs and other valuable leather goods. Sticky traps placed on horizontal surfaces will capture mature Dermestes larvae and can help locate infested materials.

FOR MORE INFORMATION
For more information about stored product pests and their control see F@stsheet Ent-1020 Recognizing and Controlling Insect Pests of Stored Products. For information about carpet beetles see Extension publication L-1736, available through your county Extension office.

Author:
Michael Merchant, Ph.D., Urban Entomologist, Texas AgriLife Extension Service

Publication information:
This publication is part of the House & Landscape Pest Series produced by the Department of Entomology, Texas A&M University, College Station, TX 77843-2475. The most recent update can be found at: http://165.95.73.17/FastSheets/Ent-1045.html . Series Editor: M. Merchant. For more information about arthropods, check out the Texas A&M Entomology Website at http://insects.tamu.edu
Last revision: 10/16/01