Editing Mite (section)

==Evolution and taxonomy==
[[File:Yellow mite (Tydeidae) Lorryia formosa 2 edit.jpg|thumb|upright|The microscopic mite ''[[Lorryia formosa]]'' ([[Tydeidae]])]]

The mites are not a defined taxon, but is used for two distinct groups of arachnids, the [[Acariformes]] and the [[Parasitiformes]]. 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 [[Phylum|phyla]] and superphyla, while the [[Internal transcribed spacer|ITS2]], and the [[18S ribosomal RNA]] and [[28S ribosomal RNA]] genes, provide clues at deeper levels.<ref name=Dhooria>{{cite book| vauthors = Dhooria MS | chapter = Molecular Biology and Acarology |title=Fundamentals of Applied Acarology | chapter-url = https://books.google.com/books?id=ktS4DQAAQBAJ&pg=PA176 |year=2016 |publisher=Springer |isbn=978-981-10-1594-6 |pages=176}}</ref>

===Taxonomy===
* Superorder '''[[Parasitiformes]]''' – ticks and a variety of mites<ref name=Beaulieu2011>{{Cite journal | title = Superorder Parasitiformes: In: Zhang, Z-Q. (ed.) Animal biodiversity: an outline of higher-level classification and survey of taxonomic richness | date = 2011 | last1 = Beaulieu | first1 = Frédéric | editor-last1 = Zhang | editor-first1 = Zhi-Qiang | journal = Zootaxa | volume = 3148 | doi = 10.11646/zootaxa.3148.1.23 | isbn = 978-1-86977-849-1 | issn = 1175-5326 | url = https://www.mapress.com/zootaxa/list/2011/3148.html | url-access = subscription }}</ref>
** [[Opilioacarida]] – a small order of large mites that superficially resemble [[harvestmen]] ([[Opiliones]]), hence their name<ref>{{cite journal | vauthors = Ballesteros JA, Santibáñez López CE, Kováč Ľ, Gavish-Regev E, Sharma PP | title = Ordered phylogenomic subsampling enables diagnosis of systematic errors in the placement of the enigmatic arachnid order Palpigradi | journal = Proceedings. Biological Sciences | volume = 286 | issue = 1917 | pages = 20192426 | date = December 2019 | pmid = 31847768 | pmc = 6939912 | doi = 10.1098/rspb.2019.2426 }}</ref><ref>{{cite journal |vauthors=Vázquez MM, Herrera IM, Just P, Lerma AC, Chatzaki M, Heller T, Král J |date=2021-09-30 |title=A new opilioacarid species (Parasitiformes: Opilioacarida) from Crete (Greece) with notes on its karyotype |url=https://www1.montpellier.inrae.fr/CBGP/acarologia/article.php?id=4449 |journal=Acarologia |volume=61 |issue=3 |pages=548–563 |doi=10.24349/acarologia/20214449 |s2cid=236270478|doi-access=free }}</ref>
** [[Holothyrida]] - small group of predatory mites native to former [[Gondwana]] landmasses
** [[Ixodida]] – ticks
** [[Mesostigmata]] – a large order of predatory and parasitic mites
*** [[Trigynaspida]] - large, diverse order
*** [[Monogynaspida]] - diverse order of parasitic and predatory mites
*** [[Sejida]] - small order of mites containing five families
* Superorder '''[[Acariformes]]''' – the most diverse group of mites
** [[Endeostigmata]] (probably [[paraphyletic]])
** [[Eriophyoidea]] – gall mites and relatives
** [[Trombidiformes]] – plant parasitic mites (spider mites, peacock 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 (formerly known as Cryptostigmata)
*** [[Astigmatina]] – stored product, fur, feather, dust, and human itch mites, etc.

===Fossil record===
[[File:Milbe cf Glaesacarus rhombeus.jpg|thumb|Mite, cf ''Glaesacarus rhombeus'', fossilised in [[Baltic amber]], [[Upper Eocene]]]]

The mite fossil record is sparse, due to their small size and low preservation potential.<ref name=":1">{{Cite journal| vauthors = Sidorchuk EA |date=2018-11-17|title=Mites as fossils: forever small?|url=https://www.tandfonline.com/doi/full/10.1080/01647954.2018.1497085|journal=International Journal of Acarology|language=en|volume=44|issue=8|pages=349–359|doi=10.1080/01647954.2018.1497085|bibcode=2018IJAca..44..349S |s2cid=92357151|issn=0164-7954|url-access=subscription}}</ref> The oldest fossils of acariform mites are from the [[Rhynie chert|Rhynie Chert]], Scotland, which dates to the early [[Devonian]], around 410 million years ago<ref>{{cite journal | vauthors = Dunlop JA, Garwood RJ | title = Terrestrial invertebrates in the Rhynie chert ecosystem | journal = Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences | volume = 373 | issue = 1739 | pages = 20160493 | date = February 2018 | pmid = 29254958 | pmc = 5745329 | doi = 10.1098/rstb.2016.0493 }}</ref><ref name=":1" /> while the earliest fossils of Parasitiformes are known from [[amber]] specimens dating to the mid-[[Cretaceous]], around 100 million years ago.<ref name=":1" /><ref name=":0">{{cite journal | vauthors = Arribas P, Andújar C, Moraza ML, Linard B, Emerson BC, Vogler AP | title = Mitochondrial Metagenomics Reveals the Ancient Origin and Phylodiversity of Soil Mites and Provides a Phylogeny of the Acari | journal = Molecular Biology and Evolution | volume = 37 | issue = 3 | pages = 683–694 | date = March 2020 | pmid = 31670799 | doi = 10.1093/molbev/msz255 | veditors = Teeling E | doi-access = free | hdl = 10261/209118 | hdl-access = free }}</ref> Most fossil acarids are no older than the [[Tertiary]] (up to 65 [[Year#mya|mya]]).<ref name="de la Fuente2003">{{cite journal | vauthors = de la Fuente J | title = The fossil record and the origin of ticks (Acari: Parasitiformes: Ixodida) | journal = Experimental & Applied Acarology | volume = 29 | issue = 3–4 | pages = 331–344 | year = 2003 | pmid = 14635818 | doi = 10.1023/A:1025824702816 | s2cid = 11271627 }}</ref>

===Phylogeny===

Members of the superorders [[Opilioacariformes]] and [[Acariformes]] (sometimes known as Actinotrichida) are mites, as well as some of the [[Parasitiformes]] (sometimes known as Anactinotrichida).<ref name=ToLweb>{{cite web |url=http://tolweb.org/Acari/2554 |title=Acari: The mites | vauthors = Walter DE, Krantz G, Lindquist E |date=13 December 1996 |publisher=Tree of Life Web Project |access-date=6 October 2017}}</ref> Recent genetic research has suggested that Acari is [[Polyphyly|polyphyletic]] (of multiple origins).<ref name="DabertWitalinski2010">{{cite journal | vauthors = Dabert M, Witalinski W, Kazmierski A, Olszanowski Z, Dabert J | title = Molecular phylogeny of acariform mites (Acari, Arachnida): strong conflict between phylogenetic signal and long-branch attraction artifacts | journal = Molecular Phylogenetics and Evolution | volume = 56 | issue = 1 | pages = 222–241 | date = July 2010 | pmid = 20060051 | doi = 10.1016/j.ympev.2009.12.020 }}</ref><ref name=Sanggaard>{{cite journal | vauthors = Sanggaard KW, Bechsgaard JS, Fang X, Duan J, Dyrlund TF, Gupta V, Jiang X, Cheng L, Fan D, Feng Y, Han L, Huang Z, Wu Z, Liao L, Settepani V, Thøgersen IB, Vanthournout B, Wang T, Zhu Y, Funch P, Enghild JJ, Schauser L, Andersen SU, Villesen P, Schierup MH, Bilde T, Wang J | display-authors = 6 | title = Spider genomes provide insight into composition and evolution of venom and silk | journal = Nature Communications | volume = 5 | pages = 3765 | date = May 2014 | pmid = 24801114 | pmc = 4273655 | doi = 10.1038/ncomms4765 | bibcode = 2014NatCo...5.3765S }}</ref><ref name=Ballesteros2022>{{cite journal | vauthors = Ballesteros JA, Santibáñez-López CE, Baker CM, Benavides LR, Cunha TJ, Gainett G, Ontano AZ, Setton EV, Arango CP, Gavish-Regev E, Harvey MS, Wheeler WC, Hormiga G, Giribet G, Sharma PP | display-authors = 6 | title = Comprehensive Species Sampling and Sophisticated Algorithmic Approaches Refute the Monophyly of Arachnida | journal = Molecular Biology and Evolution | volume = 39 | issue = 2 | date = February 2022 | pmid = 35137183 | pmc = 8845124 | doi = 10.1093/molbev/msac021 | veditors = Teeling E }}</ref><ref>{{cite journal | vauthors = Arribas P, Andújar C, Moraza ML, Linard B, Emerson BC, Vogler AP | title = Mitochondrial Metagenomics Reveals the Ancient Origin and Phylodiversity of Soil Mites and Provides a Phylogeny of the Acari | journal = Molecular Biology and Evolution | volume = 37 | issue = 3 | pages = 683–694 | date = March 2020 | pmid = 31670799 | doi = 10.1093/molbev/msz255 | quote = Taxonomically, the Acari can readily be separated into two superorders, the Acariformes and Parasitiformes, .... most acarologists would agree that both lineages are not closely related and thus Acari are not monophyletic | veditors = Teeling E | hdl = 10261/209118 | hdl-access = free }}</ref> 

Current understanding of probable chelicerate relationships, after Sharma and Gavish-Regev (2025):<ref name=":2" />

{{clade
|label1=[[Chelicerata]]
|1={{clade
|1=[[Pycnogonida]] (sea spiders) [[File:Pseudopallene_pachycheira.jpeg|100px]]
|label2=[[Prosomapoda]]
|2={{clade
|1=[[Opiliones]] (harvestmen) [[File:Nemastomella dubia 2.jpg|100px]]
|state2=dashed
|2={{clade
|state1=dashed
|state2=dashed
|1=[[Palpigradi]] (microwhip scorpions) [[File:Live Eukoenenia spelaea in its cave habitat.png|100px]]
|2={{clade
|state1=dashed
|state2=dashed
|1=[[Solifugae]] (camel spiders) [[File:USMC-050510-M-7846V-002.jpg|100px]]
|2=[[Acariformes]] [[File:Galumnidae sp.png|100px]]
}}}}
|3=[[Parasitiformes]] [[File:Promegistus armstrongi 335075066.jpg|100px]]
|4={{clade
|state1=dashed
|state2=dashed
|1=[[Xiphosura]] (horseshoe crabs) [[File:Horseshoe crab (62577).jpg|100px]]
|2=[[Ricinulei]][[File:Ricinulei_from_Fernandez_&_Giribet,_male_Ricinoides_karschii_from_Campo_Reserve,_Cameroon_(2015)_(cropped).jpg|100px]]
|label3=Arachnopulmonata
|3={{clade
|label1=Panscorpiones
|1={{clade
|1=[[Pseudoscorpiones]] (pseudoscorpions) [[File:Neobisium_sylvaticum_03.jpg|100px]]
|2=[[Scorpiones]] (scorpions) [[File:Buthus_mariefranceae_(10.3897-zookeys.686.12206)_Figure_1.jpg|100px]]
}}
|label2=[[Tetrapulmonata]]
|2={{clade
|1=[[Araneae]] (spiders) [[File:Theraphosa_blondi_MHNT.jpg|100px]]
|2={{clade
|1=[[Amblypygi]] (whip-spiders) [[File:Damon_johnstoni_–_Lydekker,_1879.png|100px]]
|2={{clade
|1= [[Schizomida]] (shorttailed whipscorpions) [[File:Hubbardia_pentapeltis_female.jpg|100px]]
|2=[[Uropygi]] (whip scorpions/vinegaroons) [[File:Whip_Scorpion_body_(9672115742)_(white_background).png|100px]]
}}}}}}}}}}}}}}}}
However, a few phylogenomic studies have found strong support for monophyly of Acari and a sister relationship between Acariformes and Parasitiformes,<ref>{{cite journal | vauthors = Lozano-Fernandez J, Tanner AR, Giacomelli M, Carton R, Vinther J, Edgecombe GD, Pisani D | title = Increasing species sampling in chelicerate genomic-scale datasets provides support for monophyly of Acari and Arachnida | journal = Nature Communications | volume = 10 | issue = 1 | pages = 2295 | date = May 2019 | pmid = 31127117 | pmc = 6534568 | doi = 10.1038/s41467-019-10244-7 | bibcode = 2019NatCo..10.2295L }}</ref><ref>{{cite journal | vauthors = Howard RJ, Puttick MN, Edgecombe GD, Lozano-Fernandez J | title = Arachnid monophyly: Morphological, palaeontological and molecular support for a single terrestrialization within Chelicerata | journal = Arthropod Structure & Development | volume = 59 | pages = 100997 | date = November 2020 | pmid = 33039753 | doi = 10.1016/j.asd.2020.100997 | bibcode = 2020ArtSD..5900997H | s2cid = 222302964 }}</ref> although this finding has been questioned, with other studies suggesting that this likely represents a [[long branch attraction]] artefact as a result of inadequate sampling.<ref name=Ballesteros2022/><ref name=":2" />