In a new house where plaster is still damp, or where damp plaster occurs in old property, very tiny, almost black beetles about 2mm long may be found. These are called plaster beetles.
Remedy:
The adults and larvae feed on microscopic moulds and mildew. They will die out if the rooms are thoroughly dried and ventilated.
Having problems with Plaster Beetles?
Use a professional pest controller.
Search for your local BPCA member
Source: A-Z