Mites (Subclass Acari)
Mites are among the most diverse and successful of all the invertebrate groups. They have exploited an incredible array of habitats, and because of their small size (most are microscopic), go largely unnoticed. Many live freely in the soil or water, but there are also a large number of species that live as parasites on plants, animals, and some that feed on mould. It is estimated that 48,200 species of mites have been described.
Mites occupy a wide range of ecological niches. In soil ecosystems, mites are favoured by high organic matter content and by moist conditions, wherein they actively engage in the fragmentation and mixing of organic matter.
The majority of mite species are harmless to humans, but a few species of mites can colonize humans directly, act as vectors for disease transmission, or cause or contribute to allergenic diseases.
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