The presence of this insect in farm-stored grain is taken as a warning that the grain is beginning to spoil and become mouldy. It is frequently associated with hot spots in farm-stored grain. Although primarily a fungivorous species, it also feeds on various other foods, especially if they are damp and mouldy. The foreign grain beetle can be separated from the rusty grain beetle, with which it is frequently associated, by its clubbed antennae, less flattened body, and the presence of a single blunt tooth on each apical corner of the prothorax. The foreign grain beetle is also a strong flier, which enables it to move freely from granary to granary and can climb glass while the rusty grain beetle cannot.
Mites are whitish and about the size of a pinhead.
They feed on stored foods such as flour, grain, seeds or bulbs or on the fungi that develop on these products. Therefore, it is most likely to find mites on grain that is tough or damp. A mite infestation will kill seeds, reduce germination and reduce the milling quality of grains. The product will often acquire a minty odour. Fumigation may be ineffective because of the unusual ability of some species of mites to survive under adverse conditions by going into a resting stage.