Plaster Beetle

Size:

1/16-inch long

Color:

Varies depending on species: brown, reddish-brown, black

Behavior:

Plaster beetles belong to the family Lathridiidae, which contains many different genera and species. These are tiny beetles for the most part and different types are shaped and colored a bit differently thus making identification by an uneducated eye more difficult. Plaster beetles may also be known as minute brown scavenger beetles or lathridiid beetles. Most plaster beetles are good fliers and may be found attracted to window sills, sinks and light fixtures. These beetles obtained their name from the time when walls in homes were constructed of wire mesh and wet plaster. Invariably, excess moisture behind wallpaper installed before walls had dried promoted mold growth, which served as food for these beetles. As populations of the beetles grew large, beetles would begin to exit from their breeding sites, often appearing by the hundreds or thousands. The life cycle of plaster beetles can be completed quickly, occurring in as few as 13 to 28 days, which results in a large numbers of beetles. Newly constructed homes and buildings use prefabricated drywall boards, therefore problems with plaster beetles are less often encountered. Because plaster beetles are fungus feeders, however, they can thrive in any building where there is a water leak, poor ventilation or other sources of moisture that permit the development of molds inside walls or other voids. Related beetles, such as the foreign grain beetle (Ahasverus advena), the silky fungus beetle (Cryptophagus laticollis), and the cellar fungus beetle (Cryptophagus cellaris) are all fungus feeders that may be found living with plaster beetles or in conditions preferred by them.