Xestobium rufovillosum, the death watch beetle, is a small (4-7 mm) wood-boring beetle in the family Anobiidae. The larvae of these beetles infest hardwood timber, but the wood must contain fungi or the beetle is not able to utilize it. Thus X. rufovillosum is found primarily in wood with moisture content greater than 14%. In forests, the death watch beetle is found in various hardwood species. When these beetles invade homes, they are found in wooden housing supports (especially oak) and heavy hardwood furniture (chestnut or oak). Death watch beetles are a common and important pest in Europe. They are also common in Eastern North America, although not nearly as important a pest species. The larvae of these beetles fill their galleries and tunnels with discrete pellets of “bun-shaped” frass, which is diagnostic of an infestation of this species. Their tunnels and exit holes are about 3mm in diameter. This pest may live for up to seven years, or complete their life-cycle in one year, if conditions are favorable. In order to attract mates, adult beetles produce a clicking/tapping noise by bumping their heads against wood, usually at night. This eerie sound was considered a superstitious death signal, and earned the beetle its common name: death watch beetle.

(Ebeling 2002; museumpests.net 2010; Wikipedia 2011)