Variegated carpet beetles: These beetles have either solid or splotchy coloring of black, white, brown, and yellow and are only 1/10-inch long. The larvae are oval or elongated in length and have brown or black bristles.Black carpet beetles: Attagenus unicolor have solid black bodies and brownish legs as an adult and vary in length from 1/8 to 3/16-inch. The larvae can vary from light yellow to golden to dark brown. The larvae bodies are tapered from the head to the posterior.Common carpet beetles: These beetles have black, white, red, and orange scales. Their larvae are reddish-brown and covered in fine hairs.
The female beetles lay soft, white eggs in concealed places on clothing, furniture, cracks in flooring, and carpet. The eggs hatch in about eight to 15 days, depending on which species, and hatch more quickly in warmer weather. Most carpet beetles typically produce four generations within a year, which is a lot when compared to black beetles, which only produce one generation per year. It is not the adult insect but the larvae that feed on fabric. They begin feeding as soon as the egg hatches. The larvae consume natural fibers such as wool, mohair, fur, and feathers and can crawl from place to place. They are most often discovered on fabric but can live in any dark crevices including air ducts, closets, and behind baseboards. Once firebrats find a food source, they tend to stay close by. These insects particularly like cotton, linen, rayon, and any starched item. Food and beverages stains that are sugar-based are particularly attractive to the firebrat. You will recognize the damage as irregular, usually following the outlines of the stain. The female moth lays up to 100 of soft, white eggs that adhere to the fabric and hatch quickly. The larvae feed for five weeks up to two years depending on humidity, temperature, and food availability. Then, they spin a case and emerge as full-grown moths in about 2 1/2 weeks. The cycle begins again, and multiple generations can be produced within a year.
