The red mite Dermanyssus gallinae
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Acarina, also called Acari, is an order of arachnids which includes mites and ticks. The body of an acarine is not segmented or divided into abdomen and prosoma. Acarine larvae usually have three pairs of legs; adults have four. The Acarina are extremely abundant animals, found almost everywhere. In terms of their economic impact they are the most important arachnid order; many species are parasitic on man or domestic animals, e.g., Sarcoptes causes scabies and the cattle tick carries babesiosis (redwater fever).