Identify black beetles, often called carpet beetles, to determine if your home or warehouse has an infestation. The larva of these insects eat natural animal fibers and dry cereals. It's common to find an occasional specimen of this variety of beetle, but the presence of several usually indicates an infestation with larvae destroying fabric or contaminating food. Preventive practices can help avoid insect population, but serious cases call for professional pest control. Look for black beetles, their larvae and food sources to ensure against infestation.
Examine the adult beetles. Adult black beetles are about 1/8-inch long with the classic oval beetle shape. The head and wings that cover the body are typically shiny black, but they may show a deep reddish brown color. The adult beetle often is seen indoors on a windowsill or carpet.
Look at the larva. These crawling worms are 1/4-inch long with bristly tufts of hair and yellowish white and brown alternating horizontal stripes. The larvae are found in dark places that supply food such as furs, silks and wool items in storage, or boxes and bags of dry cereal or ground grain.
Check the larva food supply. Damaged garments and contaminated foods will show signs of the black beetle larva. The larva molt 6 to 11 times in the course of one to three years at this developmental stage. The shed skins look just like the larva themselves. These remains distinguish black beetle larvae from moth larvae that leave webs behind on eaten fabrics.