Editing Tick (section)

===Taxonomy and phylogeny===
[[File:Tick in amber carrying spirochetes.jpg|thumb|left|Fossilized tick in Dominican [[amber]]]]

Ticks belong to the [[Parasitiformes]], a distinctive group of mites that are separate from the main group of mites, the [[Acariformes]]. Whether the two groups are more closely related to each other than to other arachnids is uncertain, and studies often recover them as not closely related.<ref>{{Cite journal|last=Giribet|first=Gonzalo|date=March 2018|title=Current views on chelicerate phylogeny—A tribute to Peter Weygoldt|url=https://linkinghub.elsevier.com/retrieve/pii/S0044523118300044|journal=Zoologischer Anzeiger|language=en|volume=273|pages=7–13|doi=10.1016/j.jcz.2018.01.004|bibcode=2018ZooAn.273....7G |s2cid=90344977 }}</ref> Within the Parasitiformes, ticks are most closely related to the [[Holothyrida]], a small group of free living scavengers with 32 described species confined to the landmasses that formed the supercontinent [[Gondwana]].<ref name=":0" />

Relationships among members of the Parasitiformes, after Klompen, 2010:<ref>{{Cite journal |last=Klompen |first=H. |date=2010-06-30 |title=Holothyrids and ticks: new insights from larval morphology and DNA sequencing, with the description of a new species of Diplothyrus (Parasitiformes: Neothyridae) |url=http://www1.montpellier.inra.fr/CBGP/acarologia/article.php?id=1970 |journal=Acarologia |volume=50 |issue=2 |pages=269–285 |doi=10.1051/acarologia/20101970 |issn=0044-586X |s2cid=55284869 |doi-access=free}}</ref>
{{clade
|label1=Parasitiformes
|1={{clade
   |1=[[Opilioacarida]]     
   |2={{clade
      |1=[[Mesostigmata]]
      |2={{clade
         |1=[[Holothyrida]]
         |2='''Ixodida''' (ticks)
         }}
      }}
   }}
}}

Fossilized ticks have been discovered from the end of the Early Cretaceous onwards, most commonly in amber. The oldest discovered tick fossils are an argasid bird tick from Late Cretaceous ([[Turonian]] ~94-90 million years ago) aged [[New Jersey amber]],<ref name="KlompenGrimaldi" /> and various ticks found in [[Burmese amber]], including ''[[Khimaira fossus|Khimaira]]'' which does not belong to any living family of tick, the living genus ''[[Nuttalliella]]'' and the possible [[Nuttalliellidae|nuttalliellid]] genera ''[[Deinocroton]]'' and ''[[Legionaris]]'',<ref name=":3">{{Cite journal |last1=Chitimia-Dobler |first1=Lidia |last2=Handschuh |first2=Stephan |last3=Dunlop |first3=Jason A. |last4=Pienaar |first4=Ronel |last5=Mans |first5=Ben J. |date=2024-04-16 |title=Nuttalliellidae in Burmese amber: implications for tick evolution |journal=Parasitology |volume=151 |issue=9 |language=en |pages=891–907 |doi=10.1017/S0031182024000477 |issn=0031-1820 |doi-access=free|pmid=38623697 |pmc=11770530 }}</ref> as well as the members of the living ixodid genera ''[[Amblyomma]]'', ''[[Ixodes]]'', ''[[Haemaphysalis]], [[Bothriocroton]]'' and ''[[Archaeocroton]]'' dating the earliest [[Cenomanian]] stage of the Late Cretaceous, around {{Ma|99}}.<ref name="PeñalverArillo2017">{{cite journal|vauthors=Peñalver E, Arillo A, Delclòs X, Peris D, Grimaldi DA, Anderson SR, Nascimbene PC, Pérez-de la Fuente R|date=December 2017|title=Ticks parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages|journal=Nature Communications|volume=8|issue=1|pages=1924|bibcode=2017NatCo...8.1924P|doi=10.1038/s41467-017-01550-z|pmc=5727220|pmid=29233973}}</ref><ref name=":0" /><ref>{{Cite journal |last1=Chitimia-Dobler |first1=Lidia |last2=Mans |first2=Ben J. |last3=Handschuh |first3=Stephan |last4=Dunlop |first4=Jason A. |date=n.d. |title=A remarkable assemblage of ticks from mid-Cretaceous Burmese amber |journal=Parasitology |volume=149 |issue=6 |language=en |pages=820–830 |doi=10.1017/S0031182022000269|pmid=35241194 |pmc=10090602 |s2cid=247227499 |issn=0031-1820|doi-access=free }}</ref><ref>{{Cite journal |last1=Chitimia-Dobler |first1=Lidia |last2=Dunlop |first2=Jason A. |last3=Pfeffer |first3=Timo |last4=Würzinger |first4=Felix |last5=Handschuh |first5=Stephan |last6=Mans |first6=Ben J. |date=February 2023 |title=Hard ticks in Burmese amber with Australasian affinities |journal=Parasitology |language=en |volume=150 |issue=2 |pages=157–171 |doi=10.1017/S0031182022001585 |issn=0031-1820 |pmc=10090639 |pmid=36341553}}</ref> An undescribed juvenile tick is known from late [[Albian]] [[amber]], dating to 105 million years ago.<ref name="PeñalverArillo2017" /> The younger [[Baltic amber|Baltic]] and [[Dominican amber]]s have also yielded examples that can be placed in living genera.<ref>{{cite journal | vauthors = Dunlop JA, Apanaskevich DA, Lehmann J, Hoffmann R, Fusseis F, Ehlke M, Zachow S, Xiao X | title = Microtomography of the Baltic amber tick Ixodes succineus reveals affinities with the modern Asian disease vector Ixodes ovatus | journal = BMC Evolutionary Biology | volume = 16 | issue = 1 | pages = 203 | date = October 2016 | pmid = 27724841 | pmc = 5057450 | doi = 10.1186/s12862-016-0777-y | doi-access = free | bibcode = 2016BMCEE..16..203D }}</ref> A phylogenetic analysis suggests that the last common ancestor of all living ticks likely lived around 195 million years ago in the Southern Hemisphere, in what was then Gondwana.<ref name=":0">{{Cite journal|last1=Beati|first1=Lorenza|last2=Klompen|first2=Hans|date=2019-01-07|title=Phylogeography of Ticks (Acari: Ixodida)|url=https://www.annualreviews.org/doi/10.1146/annurev-ento-020117-043027|journal=Annual Review of Entomology|language=en|volume=64|issue=1|pages=379–397|doi=10.1146/annurev-ento-020117-043027|pmid=30354695|s2cid=53023797|issn=0066-4170}}</ref>

Ticks belong to three different families. The majority of tick species belong to the two families: Ixodidae (hard ticks) and Argasidae (soft ticks). The third living family is [[Nuttalliellidae]], named for the bacteriologist [[George Nuttall]]. It comprises a single species, ''Nuttalliella namaqua'',<ref name="list">[[#Guglielmone|Guglielmone et al. (2010)]]</ref><ref>[[#Goddard|Goddard (2008)]]: [https://books.google.com/books?id=f-huycwyEvwC&pg=PA80 p. 80]</ref> and as such is a [[monotypic taxon]]. ''Nuttalliella namaqua'' is found in southern Africa ranging from [[Tanzania]] to [[Namibia]] and [[South Africa]].<ref name="list" /><ref>[[#Keirans|Keirans et al. (1976)]]</ref>

Relationships of living and extinct tick families, after Chitimia-Dobler et al. 2022:<ref>{{Cite journal |last1=Chitimia-Dobler |first1=Lidia |last2=Mans |first2=Ben J. |last3=Handschuh |first3=Stephan |last4=Dunlop |first4=Jason A. |date=May 2022 |title=A remarkable assemblage of ticks from mid-Cretaceous Burmese amber |journal=Parasitology |language=en |volume=149 |issue=6 |pages=820–830 |doi=10.1017/S0031182022000269 |issn=0031-1820 |pmc=10090602 |pmid=35241194}}</ref>{{clade
|label1='''Ixodida'''
|1={{clade
|1={{clade
|1={{extinct}}[[Deinocrotonidae]]
|2=[[Nuttalliellidae]]
}}
|2={{clade
|1=[[Ixodidae]]
|2=[[Argasidae]]
|3={{extinct}}[[Khimairidae]]
}}}}}}The Ixodidae contain over 700 species of hard ticks with a [[scute|scutum]] or hard shield, which the Argasidae lack. The Argasidae contain about 200 species; the genera accepted {{as of|2010|lc=y}} are ''[[Antricola]]'', ''[[Argas]]'', ''[[Nothoaspis]]'', ''[[Ornithodoros]]'', and ''[[Otobius]]''.<ref name="list" /> They have no scutum, and the [[Gnathosoma|capitulum]] (mouth and feeding parts) is concealed beneath the body.<ref name="Molyneux" /> The [[phylogeny]] of the Ixodida within the Acari is shown in the cladogram, based on a 2014 [[maximum parsimony]] study of [[amino acid]] sequences of 12 [[mitochondria]]l proteins. The Argasidae appear [[Monophyly|monophyletic]] in this study.<ref>{{cite journal | vauthors = Gu XB, Liu GH, Song HQ, Liu TY, Yang GY, Zhu XQ | title = The complete mitochondrial genome of the scab mite Psoroptes cuniculi (Arthropoda: Arachnida) provides insights into Acari phylogeny | journal = Parasites & Vectors | volume = 7 | pages = 340 | date = July 2014 | pmid = 25052180 | pmc = 4223567 | doi = 10.1186/1756-3305-7-340 | doi-access = free }}</ref>