Strange Beetles - Carpet, Flesh-Eating, Dermestid and Trilobite

Beetles are very common insects, and some very strange beetles have been discovered. The long-lived larvae of varied carpet beetles feed on natural fibers, and can destroy carpets, clothing and furniture coverings. Museums use flesh-eating beetles to strip the flesh off animal bones so that the bones can be displayed. Female trilobite beetles have a flattened body that is covered by segmented plates and reminds researchers of the ancient trilobites that once roamed the oceans.

Most beetles (but not trilobite beetles) have a pair of thick and tough forewings called elytra on the surface of their bodies. When the beetles take off for flight, they raise the elytra out of the way to reveal the more delicate, membranous hindwings underneath, which are used for flying. The elytra help to protect beetles from injury as they move over land, and are thought to be an important reason why beetles are such a successful group of insects.

The varied carpet beetle is an attractive insect in both its adult and its larval form, but the larva can be an extremely annoying and destructive pest in homes. The adults have a blotched brown, orange, yellow and white appearance. They feed on pollen and aren't pests. The adults are short-lived compared to the larvae, however. A larva is covered with brown hair-like structures called setae, and looks furry. It's often called a "woolly bear". (This term is also used for the larvae of some other insects, such as the caterpillar of certain moths.)

The varied carpet beetle larvae live between one and three years - which could be bad news, since they can feed on the natural fibers in our carpets, clothing, upholstery and tapestries. They eat animal hair and skins, leather, feathers, silk and horn as well as dead insects, other dead animals, dried meat and pet food. They also eat some plant material, including ground grains, cereals and spices.

Pest experts say that one of the best ways to prevent or get rid of a carpet beetle infestation is to follow good housekeeping practices. It’s important to vacuum clean carpets and areas where the beetles hide, such as shelves, baseboards, corners, cracks, behind radiators, in heating ducts, in furniture and along the edge of carpets. It's also important to get right to the back of a crevice with the vacuum, and the vacuum bag needs to be discarded after use. Carpet beetles may also hide in nearby wasp and bird nests.

Infested clothing needs to be thoroughly cleaned or thrown away. Heating infested items in a hot dyer for an hour or more or cooling them in a freezer for several days can kill the beetles. Once it’s certain that clothing contains no beetles, it should be stored in a sealed chest or in carefully sealed plastic bags. A serious beetle infestation may need professional help.

When museums have a mammal or bird body which they would like to "skeletonize" for display, they often place their flesh-eating beetle colony in contact with the body. Both the adults and the larvae eat flesh, but the larvae do most of the work in cleaning bones.

Flesh-eating beetles have to be used with care, because like carpet beetles they will also eat fibers from living things, including paper fibers, and they eat feathers as well. They must be kept away from books, wood, carpets and stuffed animals in museums.

The United States Fish and Wildlife Service has a Forensic Laboratory which uses beetles to skeletonize partial or damaged animal remains in order to positively identify the specimens. This can be useful in investigations related to wildlife law enforcement.

Both carpet and flesh-eating beetles belong to a family of beetles called the Dermestidae. Flesh-eating beetles are often offered for sale to the public as “Dermestid Beetles”.

Trilobite beetles are strange but little-known insects that have been found in the tropical rainforests of Southeast Asia. The body of the female trilobite beetle is flattened and is divided into segments. The beetle’s appearance reminded early observers of extinct marine animals called trilobites.

Even less is known about the male trilobite beetle than the female, but the males seems to be much smaller than the females and have a much more typical beetle appearance.

In many insects the egg hatches into a larva. There may be several larval stages, but the final larva eventually changes into a pupa, from which the adult emerges. An adult has a very different appearance from the larval forms of the insect. Female trilobite beetles are known to stay in the larval phase their whole lives, a phenomenon called neoteny.

Trilobite beetles are thought to feed on microbes in the plant liquids obtained from rotting wood. Some trilobite beetles are bioluminescent, meaning they can produce light inside their bodies. In other bioluminescent beetles, the light is produced when an enzyme breaks down a chemical called luciferin, producing energy as light. This may be the method by which trilobite beetles produce light too.

Beetles are fascinating and very successful insects. There are probably many more types still to be discovered. Perhaps some of them will be as strange as - or even stranger than - the carpet beetle, flesh-eating beetle and trilobite beetle!