Carpet beetles belong to the family Dermestidae, which derives from the Greek word for skin. As such, the main source of food for the family of beetles consists of dried animal and plant matter with high protein content, like carcasses. Carpet beetles can thrive in a variety of environments, but areas with low humidity serve the needs of developing eggs best. Consequently, most types of carpet beetles are common across Canada, the Northern United States, and Europe. The most invasive and abundant Canadian carpet beetles include the black carpet beetle (Attagenus unicolor), the Furniture carpet beetle (Anthrenus flavipes), and the varied carpet beetle (Anthrenus verbasci).
Appearance / Identification
What Does a Carpet Beetle Look Like?
Most adult carpet beetles range from 2 mm to 5 mm in length, with very short clubbed antennae and chewing mouthparts. Carpet beetles in general are oval in shape and appear dark brown to black in colour. The furniture and varied carpet beetles also bear unique, coloured scales specific to the type. White and yellow scales cover the thorax and body in distinct patterns on furniture carpet beetles. Additionally, orange and red scales run down the midline of the beetles. Varied carpet beetles feature irregular patterns of white, brown, and dark-yellow scales, which fade to solid black or brown as the insect ages.
The shape and size of carpet beetle larvae varies depending on species. However, most are elongated with varying degrees of tuft of hairs on the body. Colour ranges from dark brown to light brown. Black carpet beetle larvae are covered with short, stiff hairs and have a bristle-like tail, and the varied larvae are covered with dense tufts, which extend upright as a natural defense.
Picture of beetle larva for identification purposes
Photo example of black carpet beetle to aid in identification
View more pictures of carpet beetles
Generally, carpet beetle larvae prefer dark and secluded places. The insect often burrows in bird nests and other organic materials, such as trees and animal carcasses, when outside. Air ducts, collected lint, dry dog food, wool, and stored grains or spices often serve as both food sources and shelters while larvae grow indoors. Black and common carpet beetles do not fare as well in higher temperatures and are more prominent in Europe, the Northern United States, and Canada. While varied carpet beetles thrive further south, any place with warm buildings suits the insect. Adult carpet beetles prefer sunlight and populate gardens or other plant-heavy locations.
Carpet beetles undergo complete metamorphosis with four distinct stages: egg, larva, pupa, and adult. Females lay eggs directly on or near larval food sources, such as carpets, furs, wool, spider webs, animal carcasses, leather, and other protein-containing materials. Though timespans vary based on the type of carpet beetle and the temperature, the eggs hatch within an average of two weeks. The duration of the larval stage also depends on the type of carpet beetle species and temperature. Common carpet beetle larvae take between two and three months to reach pupation, varied carpet beetle larvae may need up to two years, and black carpet beetle larvae develop in the larval stage for six months to just under a year. Pupation for the beetles lasts around one to two weeks, and then adults live for an average of two months.
Signs of Infestation
Though carpet beetles cause the most damage during the larval stage, the first and most apparent sign of infestation is adult beetles on windowsills. Similar to moths, larvae can be detected by irregular holes found in carpets, fabric, and the like. However, carpet beetles tend to eat a single, large area of a fabric whereas moths create tiny holes all over garments. Additionally, carpet beetle larvae leave cast skins while molting, which may cause allergic reactions and dermatitis in some highly sensitive individuals.
Adult carpet beetles are often carried into houses via plants and flowers, so regularly checking gardens and flora around homes and buildings may eliminate the risk of infestation. Cleaning out collections of lint, hair, dead insects, and other debris by vacuuming helps remove the food sources of larvae and may also kill any beetles already nesting in carpets. Checking window screens, doors, and vents for durability and removing spider webs, dead animals in vents and attics, and various nests inside and around buildings are effective deterrents, as well. Additionally, homeowners benefit from frequent cleanings of rugs, draperies, upholstered furniture, closets, and stored fabrics. If serious carpet beetle infestation occurs, calling a qualified pest professional is recommended.