Deathwatch beetle, Xestobium rufovillosume

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To attract mates, these woodborers create a tapping or ticking sound that can be heard in the rafters of old buildings on quiet summer nights. They are therefore associated with quiet, sleepless nights and are named for the vigil (watch) kept beside the dying or dead, and by extension the superstitious have seen the death watch as an omen of impending death.
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