A great number of different animals may be brought into the house with cut flowers and other garden produce, and there is seldom any doubt about where they come from. It is however particularly annoying when a house or flat is suddenly found to be teeming with these small, dark beetles. The larvae live in fungi of the type that grows on stumps and fallen trees, and that may be taken home for decorative purposes. The beetles emerge from the fungi through round holes, often long after the decoration has been put aside and forgotten, and one wonders where they have come from.
Some of the fungi which attack building timber have fruiting bodies (comparable to toadstools) which these beetles could live in, so if there is no more feasible explanation for their appearance, it may be advisable to have the house examined for fungus.