Carpet beetle and woolly bear identification

How to identify carpet beetles

The Natural History Museum names three species in UK homes:

• Varied carpet beetle (*Anthrenus verbasci*): 1.5 to 3.5 mm, with a white, orange and black pattern. Long established.
• Two-spot carpet beetle (*Attagenus pellio*): 4.5 to 6 mm, very dark with two white spots, more common in the south.
• Brown carpet beetle (*Attagenus smirnovi*): 2 to 5 mm, reddish-brown, introduced in the 1970s.

The larvae are the woolly bears: small, hairy and carrot-shaped. The varied carpet beetle larva is about 4 to 4.5 mm with uneven-coloured segments. Brown carpet beetle larvae reach up to 8 mm and avoid light.

Lookalikes

• Ladybirds are far bigger and rounder, with plain spots.
• Clothes moth larvae spin silk webbing and cases; carpet beetle larvae do not. See moth treatment.
• Silverfish can resemble two-spot larvae, but silverfish are smooth and have three tail bristles. See silverfish.

Why they are indoors, and are they harmful?

Adults feed on pollen and nectar and fly indoors in late spring and summer to lay eggs. The larvae then feed on natural fibres: wool carpets, rugs, silk, fur, feathers and animal skins, as well as dead insects, pet hair and lint. They often start in undisturbed places such as under furniture, in cupboards, in the loft, or from a dead bird or old nest in the roof space.

The NHM says their damage shows up as small, clean holes, with no silk webbing, and powdery, dust-like droppings. They do not bite or spread disease. Cast skins from the larvae can irritate some people.

How to get rid of them

Find the source first. Check wardrobes, carpet edges, under furniture and the loft, including old bird or wasp nests.

• Vacuum carpets, skirting and cupboards thoroughly, then empty the bag outside.
• Wash infested clothing at the hottest temperature the label allows, or freeze small items at -18 degrees C, as the Natural History Museum suggests.
• Store wool and fur in tightly sealed plastic bags.
• Remove any bird nest or dead animal in the loft or chimney.

Brush off or kill adults you see, but the larvae are the damaging stage.

When a professional is worth it

Often not: thorough vacuuming and washing deals with most cases. A professional is worth it if beetles keep returning after cleaning, if the larvae are in fitted carpets or wall cavities you cannot reach, or if you have valuable wool rugs, antique textiles or a collection. Moth specialists often treat carpet beetles too, and the moth treatment service is a good starting point. Ask for a survey and a follow-up visit.