Because they are very small grain mites are usually only detected when the infestation is severe. The infested goods then appear to be covered with a moving layer of dust. The female is O.5 mm and the male is O.4 mm long the body is transparent white and sparsely covered with hair; the legs are pale violet. The adult mites have 4 pairs of legs, while the larvae have 3 pairs, like insects.
Mass infestation by grain mites is only possible when the stored goods are very moist. A female deposits about 20 eggs. The white, six-footed larva is 0.15 mm long. Within a period of two weeks, it passes through two eight-legged nymphal stages before becoming an adult. Occasionally the mite passes through a long very resistant stage of development between the two nymphal stages, the so- called hypopus stage.
World-wide.
Apart from grain and cereal foods, the mite also damages animal feeds, dried fruits tobacco, etc. Infestation by mites leads not only to damage caused by feeding, but also produces a bad odor and rapid deterioration of foodstuffs.