Dermestid Beetles

These critters are in the family Dermestidae of the order Coleoptera. Dermestid, or skin beetles, are scavengers feeding on a wide variety of organic matter. They are beneficial as scavengers but they are serious pests of textiles, stored foods, and museum specimens, including insect collections. The larvae are most injurious, but the adults are flower feeders and seldom cause damage. It is wise to take precautions to prevent escape.

Any sealable container may be used for culturing Dermestids and any protein may be used as a food source. Personally, I use a 10-gallon aquarium which does very well for most specimens. Dried meat, cereals, insects or fish food are suitable as food to keep the critters alive if they are not working on a specimen. Atmospheric humidity generally supplies enough moisture but I usually add a rolled up piece of paper towel which I keep damp. Culture containers may be cleaned by passing the debris through a sieve that will retain the larvae.

Two to three generations of beetles may be obtained in a year. New cultures may be started by taking a portion of an existing culture and transferring it to another culture container with fresh media, or retaining newly emerged adults and transferring them to a fresh container for mating and egg production.

I have found Dermestids to be most excellent in skeletal preparation. A carcass (either dried or fresh) can be placed in a suitable container with a dermestid culture. The dermestid larvae will clean off all remaining flesh from the bones which can then be rinsed, degreased, bleached, and assembled. They will also strip the cartilage but that is the last thing they will eat.

In the preparation of most skulls, I have found it best to strip off as much of the hide and the flesh as possible, including digging out eyeballs and the brain. This will eliminate most of the smell of decomposition while the beetles do their work. The one exception would be that of bird skulls. I have found that a good culture of beetles will strip a bird skull clean, feathers and all, in just one day, before the smell of decomposition becomes a problem.

I have found these beetles to be living in the Idaho desert in southern Idaho. By leaving a fresh carcass in the desert, one may obtain a goodly supply if one can keep other predators from eating the carcass. An easier way might be to purchase a culture of these beetles from a Biological Supply House. The cost is relatively cheap and you will get adults, larvae and eggs. I have been able to maintain my dermestid culture for about 10 years without having to replenish it from outside sources. If they have food and a little moisture, they are happy critters and easy to maintain.