mite

Minute arachnid related to the ticks. Some mites are free-living scavengers or predators. Some are parasitic, such as the itch mite (Sarcoptes scabiei), which burrows in skin causing scabies in humans and mange in dogs, and the red mite (Dermanyssus gallinae), which sucks blood from poultry and other birds. Others parasitize plants. (Order Acarina.)

The harvest mite (genus Trombicula) is harmless as an adult, but in the larval stage attacks people and animals, penetrating the skin and setting up great irritation. The red spider mite (Tetranychus telarius) is a troublesome pest in greenhouses as it feeds on plant juices. The face mite Demodex folliculorum is a microscopic and largely harmless, human parasite that lives in the follicles around the eyelids, nose, and ear canals. It has a life cycle of 14.5 days and females lay up to 25 eggs in a follicle. Demodex incidence increases with age, ranging from around 20% infestation in 20-year-olds to around 100% in 90-year-olds. A number of mites live in cheese, flour, and other foodstuffs. They are conveyed from place to place in the larval stage by attaching themselves to flies. Some mites live entirely in the water, and many are parasitic on insects. See also chigger.