Adult : Uniformly dark, or mottled, 3mm long, do not feed or fly. Larvae : yellowish-white (early instars), middle instars brownish, later instars dark brown, covered with long hairs, 6.3mm long.

Eggs (up to 80 per female) laid over several days, on food source. Larvae : development depends on conditions, and under unfavourable conditions may become dormant for up to four years! Life span of adult from 1-1 ½ months.

The most important stored produce pest from the phyto-sanitary point of view for importers /exporters, thus is the subject of strict quarantine regulations. The diapause (dormant behaviour) of the larvae makes it difficult to control. It prefers cereals and oilseeds but will feed on a variety of produce.