Common Furniture Beetle

• The one- or two-millimetre holes we see in a piece of furniture are not the insect's way in but the adult's way out: by the time they appear, the larva has already spent years inside.
• The larval cycle lasts from two to five years, and stretches out further still if the wood is dry and poor in nutrients.
• It needs a certain amount of moisture in the wood, so central heating and the dry air of modern homes have greatly reduced how often it occurs.
• This is the woodworm of furniture, and its telltale signs are exit holes of about two millimetres and the fine sawdust that falls from them.
• The holes do not indicate an active infestation: they are where the adults came out. The real damage is inside, and it can go on for years without anything showing.
• The name of its relative the deathwatch beetle comes from the sound the adult makes by tapping its head against the wood to call a mate: an audible ticking in the night-time silence of old houses, which came to be associated with death and the deathbed vigil.
• It needs wood with a certain amount of moisture, above 12%, so central heating and well-dried timber control it better than any treatment.
• It depends on symbiotic fungi and yeasts in its gut to digest cellulose.
• It is a serious threat to heritage: antique furniture, altarpieces, coffered ceilings and historic timber structures.

Skeleton type

Invertebrate - chitin exoskeleton (insect)

Habitat and environment

Dry wood of furniture, beams, frames and floorboards

Size at birth

Egg 0.55 by 0.35 mm; the larva measures 1 mm on hatching and reaches 7 mm

Sexual maturity

The adult emerges through a circular hole 1.5 to 2 mm across, does not feed and lives 2 to 4 weeks given over to mating and laying

Gestation / incubation

The eggs hatch after 3 to 5 weeks; the larva bores through the wood for 3 to 5 years and the pupa takes 6 to 8 weeks

Litter / clutch size

20 to 60 eggs per female, in groups of 2 to 4 tucked into cracks, joints and old exit holes

Sources consulted: Building Research Establishment (Reino Unido) · Instituto del Patrimonio Cultural de España · Natural History Museum de Londres · Atlas of Forest Pests · Natural History Museum, guia de identificacion de Anobium punctatum · ficha de especie · Ficha de especie de Anobium punctatum · ficha de identificacion de la especie · fichas de biologia de coleopteros xilofagos

Best time: The adults emerge from the wood in early summer, mainly in June and July, and come to light