09-10-2021-1758 - mite mites arachnid arthropod eight leg varroa scables scabies acarology ticks and mites lyme disease

 Mites are small arachnids (eight-legged arthropods). 

Mites are not a defined taxon, but the name is used for members of several groups in the subclass acari of the class Arachnida. Mites span three different groups of arachnids, the Acariformes, the Parasitiformes, and the Opilioacariformes, which have an uncertain relationship to each other. 

Most mites are tiny, less than 1 mm (0.04 in) in length, and have a simple, unsegmented body plan. Their small size makes them easily overlooked; some species live in water, many live in soil as decomposers, others live on plants, sometimes creating galls, while others again are predators or parasites. This last type includes the commercially important Varroa parasite of honey bees, as well as the scabies mite of humans. Most species are harmless to humans but a few are associated with allergies or may transmit diseases.

The scientific discipline devoted to the study of ticks and mites is called acarology.

Mites

The microscopic mite Lorryia formosa (Tydeidae)

The mites are not a defined taxon, but the name is used for members of several groups in the subclass Acari. The phylogeny of the Acari has been relatively little studied, but molecular information from ribosomal DNA is being extensively used to understand relationships between groups. The 18 S rRNA gene provides information on relationships among phyla and superphyla, while the ITS2, and the 18S ribosomal RNA and 28S ribosomal RNA genes, provide clues at deeper levels.^[1]

Taxonomy[edit]

The third edition (2009) of the standard textbook A Manual of Acarology uses a system of six orders, grouped into three superorders:^[2]

• Superorder Opilioacariformes – a small order of large mites that superficially resemble harvestmen (Opiliones), hence their name
• Superorder Parasitiformes – ticks and a variety of mites
  • Holothyrida - predatory mites from the southern hemisphere
  • Ixodida – hard ticks and soft ticks
  • Mesostigmata – bird mites, phytoseiid mites
    • Trigynaspida [Wikidata] - large, diverse order
    • Monogynaspida - diverse order of parasitic and predatory mites
• Superorder Acariformes – the most diverse group of mites
  • Trombidiformes – plant parasitic mites (spider mites, peacock mites, gall mites, red-legged earth mites, etc.), snout mites, chiggers, hair follicle mites, velvet mites, water mites, etc.
    • Sphaerolichida - small order of mites containing two families
    • Prostigmata - large order of sucking mites
  • Sarcoptiformes
    • Oribatida – oribatid mites, beetle mites, armored mites (also cryptostigmata)
    • Astigmatina – stored product, fur, feather, dust, and human itch mites, etc.

https://en.wikipedia.org/wiki/Mite