Editing Uropygi (section)

==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''.