Skin beetles, also known as carpet beetles or larder beetles, are common household insects that can be a nuisance. While the name might sound concerning, they are not interested in living human skin. Instead, they are scavengers drawn to organic materials found in homes.
Recognizing Skin Beetles
Skin beetles belong to the family Dermestidae, which includes over 1,800 species. Adult skin beetles range in size from 1 to 12 millimeters (0.04 to 0.5 inches) and have a rounded, oval-shaped body. Their coloration varies, appearing in shades of brown or black, though some species have complex patterns with scales or bristles. For instance, the larder beetle (Dermestes lardarius) has a distinctive yellowish band with six black spots across its dark brown or black forewings.
The larval stage of skin beetles is more destructive and identified by their worm-like appearance and a covering of setae (hairs), giving them a fuzzy or bristly look. Larvae are longer than adults, up to 15 millimeters (0.6 inches) in length, and their color ranges from yellow-white to dark brown. Some larvae, like those of the larder beetle, have two spine-like appendages that curve backward at their posterior end, aiding identification. The presence of shed larval skins, which are bristly and brown, is a common indicator of an infestation.
Understanding Their Habits
Skin beetles are scavengers that primarily feed on dry organic materials. Their diet includes animal products such as skin, hair, feathers, wool, leather, and dried meats. They also consume natural fibers found in carpets, clothing, and furniture, as well as stored food items like grains, cereals, and spices. Dead insects are another food source.
In natural environments, skin beetles are found in animal carcasses, bird nests, and under bark, where they scavenge on decomposing organic matter. They enter homes through means like open windows, damaged screens, or by hitching rides on secondhand furniture and cut flowers. Once inside, females lay eggs in dark, secluded spots near suitable food sources, such as air ducts, closets, or under furniture. The larvae then hatch and feed, causing damage, while adult beetles often feed on pollen and nectar outdoors, though they may be found indoors near windows. The life cycle from egg to adult can vary depending on the species and environmental conditions, ranging from as short as 40-50 days for larder beetles to over a year for varied carpet beetles.
Managing Skin Beetle Presence
Preventing skin beetle infestations involves consistent housekeeping and sealing potential entry points. Regularly vacuuming floors, carpets, and upholstery removes food sources like dead insects, pet hair, and shed skin cells. Cleaning soiled fabrics, clothing, and blankets, and drying them at high heat, kills existing eggs or larvae. Storing food items in airtight containers and keeping natural fibers like wool and silk in sealed storage limits access to food sources.
Sealing cracks and crevices in walls, foundations, and around window and door frames can prevent beetles from entering the home. If an infestation is suspected, inspect items like furniture, clothing, and packaged goods before bringing them indoors. For existing infestations, thorough cleaning of all affected areas is important. These include washing and drying infested items, disposing of heavily contaminated materials, and vacuuming thoroughly, ensuring to empty the vacuum contents outside immediately. Non-chemical treatments can be used, such as applying diatomaceous earth, a fine insect-dehydrating powder, to areas where beetles are active. A mixture of equal parts white vinegar and water can be sprayed on surfaces like carpets and shelves as a natural repellent and cleaning agent.