View source for Uropygi

{{Short description|Order of arachnids known as whip scorpions}}
{{Use Oxford spelling|date = November 2017}}
{{Use dmy dates|date=March 2023}}
{{Automatic taxobox
 | fossil_range = {{Fossil range|Carboniferous|present}}
 | name = Whip scorpions, vinegaroons
 | image = Typopeltis crucifer at Fuxing, Taoyuan 2022-06-12 (cropped).jpg
 | image_caption = ''[[Typopeltis]] crucifer''
 | taxon = Uropygi
 | authority =  [[Tamerlan Thorell|Thorell]], 1883<ref name=Harv03>
   {{cite book
    |last1=Harvey |first1=Mark S.
    |year=2003
    |contribution=Uropygi
    |title=Catalogue of the Smaller Arachnid Orders of the World: Amblypygi, Uropygi, Schizomida, Palpigradi, Ricinulei and Solifugae
    |place=Canberra, AU
    |publisher=CSIRO Publishing
    |isbn=978-0-643-09007-1
    |doi=10.1071/9780643090071
   }}
</ref><ref name=WAM>
   {{cite web
    |title=Uropygi {{small|(Thorell, 1883)}}
    |series=Field Guides & Catalogues
    |website=[[Western Australian Museum]]
    |publisher=[[Western Australian Museum]], [[Government of Western Australia]]
    |url=https://museum.wa.gov.au/catalogues-beta/whip-scorpions/order/uropygi
    |access-date=2023-03-10
   }}
</ref>
 | synonyms = Thelyphonida <small>Latreille, 1804</small> (as Thélyphone)
 | synonyms_ref = <ref name=Harv03/><ref name=WAM/>
 | diversity_link = List of Thelyphonidae species
 | diversity = {{circa|23}}&nbsp;genera, over 100&nbsp;species
 | subdivision_ranks = Families
 | subdivision = *[[Thelyphonidae]]
 | range_map = Uropygi Distribution Map.png
 | range_map_caption = Distribution map of Uropygi
}}

'''Uropygi''' is an [[arachnid]] order comprising invertebrates commonly known as '''whip scorpions''' or '''vinegaroons''' (also spelled '''vinegarroons''' and '''vinegarones'''). They are often called '''uropygids'''. The name "whip scorpion" refers to their resemblance to [[scorpion|true scorpion]]s and possession of a whiplike tail, and "vinegaroon" refers to their ability when attacked to discharge an offensive, [[vinegar]]-smelling liquid, which contains [[acetic acid]]. The order may also be called '''Thelyphonida'''. Both names, Uropygi and Thelyphonida, may be used either in a narrow sense for the order of whip scorpions, or in a broad sense which includes the order [[Schizomida]].{{efn|
For clarity, ''[[sensu stricto]]'' or ''s.s.'' may be added to specify the narrow sense, and ''[[sensu lato]]'' or ''s.l.'' added to specify the broad sense. When these additions are omitted, the names Uropygi and Thelyphonida are ambiguous.
}}

==Taxonomy==
[[Carl Linnaeus]] first described a whip scorpion in 1758, although he did not distinguish it from what are now regarded as different kinds of arachnid, calling it ''Phalangium caudatum''. ''[[Phalangium]]'' is now used as a name for a genus of harvestmen ([[Opiliones]]). In 1802, [[Pierre André Latreille]] was the first to use a genus name solely for whip scorpions, namely ''[[Thelyphonus]]''.<ref name=Harv02/><ref name=Latr02/> Latreille later explained the name as meaning "''{{lang|fr|qui tue}}''", meaning "who kills".<ref name=Latr04/>{{efn|
In [[Ancient Greek|Greek]] {{lang|grc|[[wikt:φόνος|{{math|φόνος}}]]}}, ''phonos'', means "murder", while {{lang|grc|{{math|φονός}} }}, with final accent, can be an adjective meaning "murderous", but also a noun meaning "murderess"; Latreille did not account for the element {{lang|grc|[[wikt:θῆλυς|{{math|θῆλυς}}]]}}, ''thelys'', meaning "female".
}}
One name for the order, Thelyphonida, is based on Latreille's genus name. It was first used, as the French {{lang|fr|Thélyphone}}, by Latreille in 1804,<ref name=Harv03/> and later by [[Octavius Pickard-Cambridge]] in 1872 (with the spelling Thelyphonidea).<ref name=Camb72/>

The alternative name, Uropygi, was first used by [[Tamerlan Thorell]] in 1883.<ref name=Harv03/> It means "tail rump", from [[Ancient Greek]] {{lang|el|{{math|οὐροπύγιον}} }} (''{{lang|el|ouropygion}}''),<ref>{{cite book |author=[[Aristotele]] |url=https://books.google.com/books?id=sUfySpLBb2wC&pg=PA109-IA3 |title=De Anim. Hist. | date=28 November 2023 |at=Lib: IV Cap: I}}</ref> from {{lang|grc|{{math|οὐρά}} }} (''{{lang|el|oura}}'') "tail" and {{lang|grc|{{math|πυγή}} }} (''{{lang|el|pygē}}'') "rump" referring to the whip-like [[flagellum]] on the end of the [[pygidium]], a small plate made up of the last three segments of the abdominal [[exoskeleton]].

The classification and scientific name used for whip scorpions varies. Originally, [[Amblypygi]] (whip spiders), Uropygi and [[Schizomida]] (short-tailed whipscorpions) formed a single order of arachnids, Pedipalpi. Pedipalpi was later divided into two orders, Amblypygi and Uropygi (or Uropygida). Schizomida was then split off from Uropygi into a separate order.<ref name=Garw/> The remainder has either continued to be called by the same name, Uropygi,<ref name=Harv02/> possibly distinguished as Uropygi ''[[sensu stricto]]'', or called Thelyphonida.<ref name=Garw/> When the name Uropygi is used for the whip scorpions, the clade containing Uropygi and Schizomida may be called Thelyphonida,<ref>{{fossilworks |id=276198 |title=Order Thelyphonida {{small|(Latreille, 1804)}} (whip scorpion) |date=2023-03-10}}</ref> or Thelyphonida ''[[sensu lato|s.l.]]'' Conversely, when the name Thelyphonida is used for the whip scorpions alone, the parent clade may be called Uropygi,<ref>{{cite web |title=order Uropygi {{small|(Thorell, 1883)}} |website=BioLib |url=https://www.biolib.cz/en/taxon/id16785 |access-date=2023-03-10}}</ref> or Uropygi ''[[sensu lato]]''. The table below summarizes the two usages. When the qualifications ''[[sensu lato|s.l.]]'' and ''[[sensu stricto|s.s.]]'' are omitted, the names Uropygi and Thelyphonida are ambiguous.<!-- yes, this is an editorial comment, but I think necessary in the context -->

{| class="wikitable"
|+ Alternative nomenclature
|-
!English names !! System 1 !! System 2 !! Recent families
|-
|  || Thelyphonida ''s.l.'' (if used) || Uropygi ''s.l.'' (if used) ||
|-
| whip scorpions ||Uropygi ''s.s.'' ||Thelyphonida ''s.s.'' || [[Thelyphonidae]]
|-
| short-tailed whip scorpions ||Schizomida ||Schizomida || [[Hubbardiidae]], [[Protoschizomidae]]
|}

Phylogenetic studies show the three groups, Amblypygi, Uropygi ''[[sensu stricto|s.s.]]'' and Schizomida, to be closely related.<ref name=Garw>{{cite journal |title=Three-dimensional reconstruction and the phylogeny of extinct chelicerate orders |first1=Russell J. |last1=Garwood |first2=Jason A. |last2=Dunlop |date=2014 |journal=PeerJ |volume=2 |pages=e641 |doi=10.7717/peerj.641 |pmid=25405073 |pmc=4232842 |doi-access=free }}</ref><ref name=Shul07>{{cite journal |first=Jeffrey W. |last=Shultz |year=2007 |title=A phylogenetic analysis of the arachnid orders based on morphological characters |journal=Zoological Journal of the Linnean Society |volume=150 |issue=2 |pages=221–265 |doi=10.1111/j.1096-3642.2007.00284.x|doi-access=free }}</ref> The Uropygi ''[[sensu stricto|s.s.]]'' and Schizomida likely diverged in the late [[Carboniferous]], somewhere in the tropics of [[Pangaea]].<ref name=Clou17>{{Cite journal |last1=Clouse |first1=Ronald M. |last2=Branstetter |first2=Michael G. |last3=Buenavente |first3=Perry |last4=Crowley |first4=Louise M. |last5=Czekanski‐Moir |first5=Jesse |last6=General |first6=David Emmanuel M. |last7=Giribet |first7=Gonzalo |last8=Harvey |first8=Mark S. |last9=Janies |first9=Daniel A. |display-authors=6 |year=2017 |title=First global molecular phylogeny and biogeographical analysis of two arachnid orders (Schizomida and Uropygi) supports a tropical Pangean origin and mid-Cretaceous diversification |journal=[[Journal of Biogeography]] |volume=44 |issue=11 |pages=2660–2672 |doi=10.1111/jbi.13076 |doi-access= |issn=1365-2699 |language=en}}</ref>
{{clade
 |style=line-height:100%
 |label1={{nobr|&emsp; [[Pedipalpi]] &emsp;}}
 |1={{clade
   |1={{clade <!--dummy to align text of sister clades-->
      |label1={{nobr|&emsp; Amblypygi &emsp;}}
      |1=whip spiders [[File:Flickr - ggallice - Tailless whip-scorpion, La Muerta.png|120px]]
      }}
   |2={{clade
      |label1={{nobr|&emsp; Thelyphonida ''s.l.'' &emsp;}}
      |sublabel1=(Uropygi ''s.l.'')
      |1={{clade
         |label1=Uropygi ''s.s.''
         |sublabel1={{nobr|&emsp; (Thelyphonida ''s.s.'') &emsp;}}<br/>
         |1=whip scorpions [[File:Whip Scorpion body (9672115742) (white background).png|80px]]
         |label2={{nobr|&emsp; Schizomida &emsp;}}
         |2=short-tailed whip scorpions [[File:Brignolizomus woodwardi 175486060.jpg|80px]]
         }}
      }}
   }}
}}

==Description==
Whip scorpions range from {{convert|25|to|85|mm|1|abbr=on}} in length, with most species having a body no longer than {{convert|30|mm|abbr=on}}; the largest species, of the genus ''[[Mastigoproctus]]'', can reach {{convert|85|mm|abbr=on}}.<ref name=schmidt93>{{cite book |author=Schmidt, Günther |year=1993 |title=Giftige und gefährliche Spinnentiere |language=de |trans-title=Poisonous and dangerous arachnids |publisher=Westarp Wissenschaften |isbn=978-3-89432-405-6}}</ref> An extinct ''[[Mesoproctus]]'' from the [[Lower Cretaceous]] [[Crato Formation]] could be the same size.<ref>{{cite journal |first1=Jason A. |last1=Dunlop |first2=David M. |last2=Martill |year=2002 |title=The first whipspider (Arachnida: Amblypygi) and three new whipscorpions (Arachnida: Thelyphonida) from the Lower Cretaceous Crato Formation of Brazil |journal=Transactions of the Royal Society of Edinburgh: Earth Sciences |volume=92 |issue=3 |pages=325–334 |doi=10.1017/S0263593300000262 |s2cid=140573577 |url=https://d-nb.info/1216876800/34 |format=PDF}}</ref> Because of their legs, claws, and "whip", though, they can appear much larger, and the heaviest specimen weighed was 12.4 grams (0.44&nbsp;oz).<ref>{{cite book |last=Glenday |first=Craig |year=2013  |title=Guinness World Records 2014 |isbn=978-1-908843-15-9 |pages=[https://archive.org/details/guinnessworldrec0000unse_r3e7/page/33 33] |publisher=Guinness World Records Limited |url=https://archive.org/details/guinnessworldrec0000unse_r3e7/page/33}}</ref>

The [[opisthosoma]] consists of 12&nbsp;segments. The first segment forms a pedicel, and each of the next eight segments has dorsal [[Tergum|tergites]]. The last three segments are fused into closed rings, forming a [[pygidium]] that ends with a flagellum of 30–40 units.<ref>{{cite book |editor1=Minelli, Alessandro |editor2=Contrafatto, Giancarlo |date=10 Nov 2009 |title=Biological Science Fundamentals and Systematics |volume=III |page=225 |place=Oxford, UK |publisher=EOLSS Publications |series=Encyclopedia of Life Support Systems |isbn=978-1-84826-990-3 |url=https://books.google.com/books?id=8ZnEDAAAQBAJ&dq=Uropygi+pedicel+abdomen&pg=PA225 |via=Google Books}}</ref><ref>{{cite book |author=Ax, Peter |year=2000 |edition=English |orig-year=1999 original German ed. |title=Multicellular Animals: The phylogenetic system of the metazoa |volume=II: The Phylogenetic System of the Metazoa |page=103 |translator=Kiney, S. |publisher=Springer |isbn=978-3-642-08681-6 |doi=10.1007/978-3-662-10396-8 |s2cid=28516278 |url=https://books.google.com/books?id=x7vtCAAAQBAJ&dq=%22Only+the+last+three+segments+form+closed+rings%22&pg=PA103 |via=Google Books}}</ref>

Like the related orders Schizomida and Amblypygi, whip scorpions use only six legs for walking, with the first two legs serving as antennae-like sensory organs. All species also have very large scorpion-like [[pedipalp]]s (pincers) but there is an additional large spine on each palpal tibia. They have one pair of median eyes at the front of the [[cephalothorax]] and up till five pairs of lateral eyes on each side of the head, a pattern also found in scorpions.<ref>{{cite conference |author=Weygoldt, Peter |date=1–5 July 1996 |title=Evolution and systematics of the Chelicerata |editor1=Bruin, J. Leo |editor2=van der Geest, P.S. |editor3=Sabelis, M.W. |book-title=Ecology and Evolution of the Acari |publication-date=1999 |pages=1–5, esp. p&nbsp;5 |conference=3rd Symposium of the European Association of Acarologists |place=Amsterdam, NL |isbn=978-90-481-5200-1 |doi=10.1007/978-94-017-1343-6 |url=https://books.google.com/books?id=gcX0CAAAQBAJ&dq=%22Whip+scorpions%22+five+pairs+lateral+eyes&pg=PA5 |via=Google Books|url-access=subscription }}</ref><ref>{{cite report |title=Invertebrates |first1=Richard C. |last1=Brusca |first2=Gary J. |last2=Brusca |page=505 |website=juristas.com.br |url=https://juristas.com.br/wp-content/uploads/pdf-results/juristas-5aa181ee19460.pdf}}</ref> Whip scorpions have no [[venom]] glands, but they have glands near the rear of their abdomen that can spray a combination of acetic acid and [[caprylic acid]] when they are bothered.<ref name=schmidt93/> The acetic acid gives this spray a vinegar-like smell, giving rise to the common name ''vinegaroon''.

==Behaviour==

[[File:Vinegaroon - Mastigoproctus giganteus with Slate Millipede.jpg|thumb|''[[Mastigoproctus giganteus]]'', a predator of millipedes]]
Whip scorpions are [[carnivorous]], nocturnal hunters feeding mostly on [[insect]]s, [[millipede]]s, scorpions, and terrestrial isopods,<ref name=schmidt93/> but sometimes on worms and slugs. ''Mastigoproctus'' sometimes preys on small [[vertebrate]]s.<ref name=schmidt93/> The prey is crushed between special teeth on the inside of the trochanters (the second segment of the "legs") of the front appendages. They are valuable in controlling the population of cockroaches and crickets.

Males secrete a [[spermatophore]] (a united mass of sperm), which is transferred to the female following courtship behaviour, in which the male holds the ends of the female's first legs in his [[chelicerae]]. The spermatophore is deposited on the ground and picked up by the female using her genital area. In some genera, the male then uses his pedipalps to push the spermatophore into her body.<ref name=RuppFoxBarn04p569/>

[[File:Mastigoproctus giganteus 0008 L.D.jpg|thumb|''Mastigoproctus giganteus'' female with eggs]]
After a few months, the female will dig a large burrow and seal herself inside. Up to 40 eggs are [[wiktionary:extrude|extruded]], within a membranous broodsac that preserves moisture and remains attached to the genital [[operculum (animal)|operculum]] and the fifth segment of the mother's ventral [[opisthosoma]]. The female refuses to eat and holds her opisthosoma in an upward arch so that the broodsac does not touch the ground for the next few months, as the eggs develop into [[wiktionary:postembryo|postembryos]]. Appendages become visible.<ref name=McMonigle-2017>{{cite book |first=Orin |last=McMonigle |date=November 2017 |title=Whipscorpions and Whipspiders: Culturing gentle monsters |publisher=Elytra and Antenna |isbn = 978-098024012-2}}</ref>

The white young that hatch from the postembryos climb onto their mother's back and attach themselves there with special suckers. After the first [[Moulting|moult]], when they look like miniature adults but with bright red palps, they leave the burrow. The mother may live up to two more years. The young grow slowly, going through four moults in about four years before reaching adulthood. They live for up to another four years.<ref name=schmidt93/><ref name=McMonigle-2017/>

==Distribution and habitat==
Whip scorpions are found in [[tropical]] and [[subtropical]] areas, excluding [[Europe]] and [[Australia]]. Also, only a single species is known from [[Africa]]: ''[[Etienneus africanus]]'', probably a [[Gondwana]] [[Relict (biology)|relict]], endemic to [[Senegal]], [[the Gambia]] and [[Guinea-Bissau]].<ref>{{cite journal |author1=Huff, Jeremy C. |author2=Prendini, Lorenzo |year=2009 |title=On the African whip scorpion, ''Etienneus africanus'' {{small|(Hentschel, 1899)}} (Thelyphonida: Thelyphonidae), with a redescription based on new material from Guinea-Bissau and Senegal |journal=[[American Museum Novitates]] |issue=3658 |pages=1–16 |doi=10.1206/674.1 |hdl=2246/5981 |s2cid=59942800 |url=https://www.biodiversitylibrary.org/bibliography/169014 }}</ref> 

They usually dig burrows with their pedipalps, to which they transport their prey.<ref name=schmidt93/> They may also burrow under logs, rotting wood, rocks, and other natural debris. They prefer humid, dark places and avoid light. ''[[Mastigoproctus giganteus]]'', the giant whip scorpion, is found in more arid areas, including Arizona and New Mexico.<ref>{{cite web |title=Giant whip scorpion ''Mastigoproctus giganteus giganteus'' {{small|(Lucas, 1835)}} |website=Featured Creatures |series=Institute of Food and Agricultural Sciences, Department of Entymology |publisher=[[University of Florida]] |url=http://entnemdept.ufl.edu/creatures/misc/misc/giant_whip_scorpion.htm |access-date=2016-08-01 }}</ref>

==Subtaxa==
{{Main|List of Thelyphonidae species}}
As of 2023, the ''World Uropygi Catalog'' accepted the following 16&nbsp;extant genera, all placed in the family Thelyphonidae:<ref name="NMBE">{{cite web |year=2024 |title=World Uropygi Catalog |url=https://wac.nmbe.ch/order/uropygi/7 |access-date=9 December 2024 |publisher=[[Natural History Museum, Bern|Natural History Museum]] |place=Bern, CH}}</ref>

{{Div col|colwidth=24em}}
* ''[[Etienneus]]'' <small>Heurtault, 1984</small>
* ''[[Ginosigma]]'' <small>Speijer, 1936</small>
* ''[[Glyptogluteus]]'' <small>Rowland, 1973</small>
* ''[[Hypoctonus]]'' <small>Thorell, 1888</small>
* ''[[Labochirus]]'' <small>Pocock, 1894</small>
* ''[[Mastigoproctus]]'' <small>Pocock, 1894</small>
* ''[[Mayacentrum]]'' <small>Viquez & Armas, 2006</small>
* ''[[Mimoscorpius]]'' <small>Pocock, 1894</small>
* ''[[Ravilops]]'' <small>Víquez & Armas, 2005</small>
* ''[[Sheylayongium]]'' <small>Teruel, 2018</small>
* ''[[Thelyphonellus]]'' <small>Pocock, 1894</small>
* ''[[Thelyphonoides]]'' <small>Krehenwinkel, Curio, Tacud & Haupt, 2009</small>
* ''[[Thelyphonus]]'' <small>Latreille, 1802</small>
* ''[[Typopeltis]]'' <small>Pocock, 1894</small>
* ''[[Uroproctus]]'' <small>Pocock, 1894</small>
* ''[[Valeriophonus]]'' <small>Viquez & Armas, 2005</small>
{{div col end}}

In addition, seven extinct genera were accepted, two within the family Thelyphonidae:<ref name="NMBE"/>
* †''[[Mesoproctus]]'' <small>Dunlop, 1998</small>
* †''[[Mesothelyphonus]]'' <small>Cai & Huang, 2017</small>
and five unplaced as to family:<ref name="NMBE"/>
* †''[[Burmathelyphonia]]'' <small>Wunderlich, 2015</small>
* †''[[Geralinura]]'' <small>Scudder, 1884</small>
* †''[[Inmontibusichnus]]'' <small>Knecht, Benner, Dunlop & Renczkowski, 2023</small>
* †''[[Parageralinura]]'' <small>Tetlie & Dunlop, 2008</small>
* †''[[Parilisthelyphonus]]'' <small>Knecht, Benner, Dunlop & Renczkowski, 2023</small>
* †''[[Proschizomus]]'' <small>Dunlop & Horrocks, 1996</small>
* †''[[Prothelyphonus]]'' <small>Frič, 1904</small>

==Notes==
{{Notelist}}

==References==
{{Reflist|32em|refs=

<ref name=Camb72>
{{cite journal |last=Cambridge |first=O.P. |year=1872 |title=On a new family and genus and two new species of Thelyphonidea |journal=[[Annals and Magazine of Natural History]] |volume=10 |issue=60 |series=4 |pages=409–413 |doi=10.1080/00222937208696729 |url=https://www.biodiversitylibrary.org/page/25172652 |access-date=2016-04-03}}
</ref>

<ref name=Harv02>
{{cite journal |first=M.S. |last=Harvey |year=2002 |title=The neglected cousins: What do we know about the smaller arachnid orders? |journal=[[Journal of Arachnology]] |volume=30 |issue=2 |pages=357–372 |doi=10.1636/0161-8202(2002)030[0357:TNCWDW]2.0.CO;2 |s2cid=59047074 |url=http://www.americanarachnology.org/JoA_Congress/JoA_v30_n2/arac-30-02-357.pdf |archive-url=https://web.archive.org/web/20120207165733/http://www.americanarachnology.org/JoA_Congress/JoA_v30_n2/arac-30-02-357.pdf |archive-date=2012-02-07}}
</ref>

<ref name=Latr02>
{{cite book |last=Latreille |first=Pierre A. |year=1802 |contribution=Genre Thélyphone |title=Histoire naturelle générale et particulière des Crustacés et des Insectes |volume=3 |publisher=Dufart |location=Paris, FR |page=47 |contribution-url=https://www.biodiversitylibrary.org/page/24884903 |language=fr }}
</ref>

<ref name=Latr04>
{{cite book |last=Latreille |first=Pierre A. |year=1804 |contribution=Genre Thélyphone |title=Histoire naturelle générale et particulière des Crustacés et des Insectes |volume=7 |publisher=Dufart |location=Paris, FR |pages=130–132 |contribution-url=https://www.biodiversitylibrary.org/page/24883087 |language=fr }}
</ref>

<ref name=RuppFoxBarn04p569>
{{cite book |last1=Ruppert |first1=E.E. |first2=R.S. |last2=Fox |first3=R.D. |last3=Barnes |name-list-style=amp |year=2004 |title=Invertebrate Zoology |publisher=Brooks/Cole |edition=7th |isbn=978-0-03-025982-1 |pages=[https://archive.org/details/isbn_9780030259821/page/569 569–570] |url-access=registration |url=https://archive.org/details/isbn_9780030259821/page/569 }}
</ref>

}} <!-- end "refs=" -->

==External links==
{{Commons category|Thelyphonida}}

{{Portal|Arthropods}}
{{Arachnida}}
{{Taxonbar|from=Q19135}}
{{Authority control}}

[[Category:Uropygi| ]]
[[Category:Arachnid orders]]
[[Category:Extant Pennsylvanian first appearances]]
[[Category:Carboniferous arachnids]]
[[Category:Permian arachnids]]
[[Category:Mesozoic arachnids]]
[[Category:Cenozoic arachnids]]