Centipede: Difference between revisions

'''Centipedes''' (from [[Neo-Latin]] {{lang|la|[[wikt:centi-|centi-]]}}, "hundred", and [[Latin language|Latin]] {{lang|la|[[:wikt:pes|pes, pedis]]}}, "[[foot]]") are [[predator]]y [[arthropod]]s belonging to the class '''Chilopoda''' ([[Ancient Greek]] {{lang|grc|[[:wikt:χεῖλος|χεῖλος]]}}, ''kheilos'', "lip", and [[Neo-Latin]] suffix {{lang|la|[[wikt:-poda|-poda]]}}, "foot", describing the [[forcipules]]) of the subphylum [[Myriapoda]], an arthropod group which includes [[millipede]]s and other multi-legged animals. Centipedes are elongated segmented ([[Metamerism (biology)|metameric]]) creatures with one pair of legs per body segment. All centipedes are [[venom]]ous and can inflict painful [[centipede bite|stings]], injecting their [[venom]] through [[Pincer (biology)|pincer-like]] [[appendages]] known as [[forcipules]] or toxicognaths, which are actually modified legs instead of [[fangs]]. Despite the name, no centipede has exactly 100 pairs of legs; the number of pairs of legs is an odd number that ranges from 15 pairs to 191 pairs,.<ref name="Edgecombe Giribet 2007"/> always an odd number.

Their size ranges from a few millimetres in the smaller [[Lithobiomorpha|lithobiomorphs]] and [[Geophilomorpha|geophilomorphs]] to about {{convert|30|cm|abbr=on}} in the largest [[Scolopendromorpha|scolopendromorphs]].<ref name="Minelli Golovatch 2017">{{cite book |last1=Minelli |first1=A. |last2=Golovatch |first2=S.I. |title=Reference Module in Life Sciences |chapter=Myriapods |publisher=Elsevier |year=2017 |doi=10.1016/b978-0-12-809633-8.02259-7|isbn=978-0-12-809633-8 }}</ref>

[[File:Centipede_ultimate_legs_collage.jpg|thumb|A collage showing the ultimate legs of various centipedes. From top left, proceeding clockwise: ''[[Rhysida]]'' spp., ''[[Scolopocryptops]] trogloclaudatus, [[Scolopendra dehaani|Scolopenda dehaani]], [[Lithobius proximus]], [[Lithobius forficatus]], [[Scolopendra cingulata]].'']]

Just as the first pair of legs are modified into forcipules, the back legs are modified into "ultimate legs", also called anal legs, caudal legs, and terminal legs.<ref>{{Cite journal |last1=Bonato |first1=Lucio |last2=Edgecombe |first2=Gregory |last3=Lewis |first3=John |last4=Minelli |first4=Alessandro |last5=Pereira |first5=Luis |last6=Shelley |first6=Rowland |last7=Zapparoli |first7=Marzio |date=2010-11-18 |title=A common terminology for the external anatomy of centipedes (Chilopoda) |journal=ZooKeys |issue=69 |pages=17–51 |doi=10.3897/zookeys.69.737 |issn=1313-2970 |pmc=3088443 |pmid=21594038|doi-access=free |bibcode=2010ZooK...69...17B }}</ref> Their use varies between species, but does not include locomotion.<ref name=":0">{{Cite journal |last1=Kenning |first1=Matthes |last2=Müller |first2=Carsten H. G. |last3=Sombke |first3=Andy |date=2017-11-14 |title=The ultimate legs of Chilopoda (Myriapoda): a review on their morphological disparity and functional variability |journal=PeerJ |volume=5 |pages=e4023 |doi=10.7717/peerj.4023 |pmid=29158971 |pmc=5691793 |issn=2167-8359 |doi-access=free }}</ref><ref name=":1">{{Cite journal |last1=Kenning |first1=Matthes |last2=Schendel |first2=Vanessa |last3=Müller |first3=Carsten H. G. |last4=Sombke |first4=Andy |date=2019 |title=Comparative morphology of ultimate and walking legs in the centipede Lithobius forficatus (Myriapoda) with functional implications |journal=Zoological Letters |volume=5 |pages=3 |doi=10.1186/s40851-018-0115-x |issn=2056-306X |pmc=6330759 |pmid=30656061 |doi-access=free }}</ref> The ultimate legs may be elongated and thin, thickened, or pincer-like.<ref name=":1"/> They are frequently [[Sexual dimorphism|sexually dimorphic]], and may play a role in mating rituals.<ref name=":0"/><ref name=":1"/> Because glandular pores occur more frequently on ultimate legs than on the "walking" legs, they may serve a sensory role.<ref name=":0"/><ref name=":1"/> They are sometimes used in defensive postures, and some species use them to capture prey, defend themselves against predators, or suspend themselves from objects such as branches, using the legs as pincers.<ref name=":0"/> Several species use their ultimate legs upon encountering another centipede, trying to grab the body of the other centipede.<ref name=":2"/>

ScholarsThere haveare notedmany that disinformation exists about the differencedifferences between millipedes and centipedes, and they seek to provide more generalized information for education purposes.<ref name="Shelley 1999">{{cite journal |last=Shelley |first=Rowland M. |title=Centipedes and millipedes with emphasis on North American fauna |journal=The Kansas School Naturalist |year=1999 |volume=45 |issue=3 |pages=1–16 |url=http://www.emporia.edu/ksn/v45n3-march1999/ |access-date=2013-10-14 |archive-url=https://web.archive.org/web/20161112025334/http://www.emporia.edu/ksn/v45n3-march1999/ |archive-date=2016-11-12 |url-status=dead }}</ref> Both groups of myriapods have long, multi-segmented bodies, many legs, a single pair of antennae, and the presence of [[Tömösváry organ|postantennal organ]]s. Centipedes have one pair of legs per segment, while millipedes have two. Their heads differ in that millipedes have short, elbowed [[Antenna (biology)|antenna]]e, a pair of robust mandibles and a single pair of maxillae fused into a lip; centipedes have long, threadlike antennae, a pair of small mandibles, two pairs of maxillae and a pair of large venom claws.<ref name=Blower>{{cite book|author=Blower, John Gordon |title=Millipedes: Keys and Notes for the Identification of the Species |url=https://books.google.com/books?id=VQsVAAAAIAAJ&pg=PA1 |year=1985 |publisher=Brill Archive |isbn=978-90-04-07698-3 |page=1}}</ref>

Centipedes grow their legs at different points in their development. In the primitive condition, seen in the orders [[Lithobiomorpha]], [[Scutigeromorpha]], and [[Craterostigmomorpha]], development is [[Anamorphosis (biology)|anamorphic]]: more segments and pairs of legs are grown between [[ecdysis|moults]].<ref>{{cite journal |last=Fusco |first=Giuseppe |title=Trunk segment numbers and sequential segmentation in myriapods. |journal=Evolution & Development |date=December 2005 |volume=7 |issue=6 |pages=608–617 |doi=10.1111/j.1525-142X.2005.05064.x |pmid=16336414 |s2cid=21401688 |url=https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1525-142X.2005.05064.x |access-date=25 August 2020}}</ref> For example, ''[[Scutigera coleoptrata]]'', the house centipede, hatches with only four pairs of legs and in successive moults has 5, 7, 9, 11, 15, 15, 15 and 15 pairs respectively, before becoming a sexually mature adult. Life stages with fewer than 15 pairs of legs are called larval stadia (there are about five stages). After the full complement of legs is achieved, the now postlarval stadia (about five more stages) develop gonopods, sensory pores, more antennal segments, and more ocelli. All mature lithobiomorph centipedes have 15 leg-bearing segments.{{sfn|Lewis|2007|p=27}} The Craterostigmomorpha only have one phase of anamorphosis, with embryos having 12 pairs, and adults 15.<ref name="Edgecombe Giribet 2007"/>

The [[clade]] Epimorpha, consisting of the orders [[Geophilomorpha]] and [[Scolopendromorpha]], is epimorphic, meaning that all pairs of legs are developed in the embryonic stages, and offspring do not develop more legs between moults. This clade contains the longest centipedes;. In the maximumGeophilomorpha, the number of [[Thorax (arthropod anatomy)|thoracic]] segments usually varies within species, often on a geographical basis, and in most cases, females bear more legs than males. The number of leg-bearing segments invaries thesewithin groupseach variesorder (usually 21 or 23 in the Scolopendromorpha; from 1527 to 191, butin the developmentalGeophilomorpha),<ref modename=":5">{{Citation of|title=Chilopoda their– creationTaxonomic isoverview [[Evolutionary|date=2011-01-01 developmental|work=Treatise biology#Developmentalon bias|constrained]]Zoology so- thatAnatomy, theyTaxonomy, areBiology. alwaysThe addedMyriapoda, inVolume pairs1 |pages=363–443 |url=https://brill.com/display/book/edcoll/9789004188266/B9789004188266_020.xml The|access-date=2024-02-29 |publisher=Brill |language=en |doi=10.1163/9789004188266_020 |isbn=978-90-04-18826-6 |editor-last1=Minelli |editor-first1=Alessandro }}</ref> but the total number of pairs beginsis and remainsalways odd throughout development, so there are never exactly 100 legs or 100 pairs, despite the group's common name.<ref name="Edgecombe Giribet 2007">{{cite journal |last1=Edgecombe |first1=Gregory D. |last2=Giribet |first2=Gonzalo |title=Evolutionary biology of centipedes (Myriapoda: Chilopoda) |journal=[[Annual Review of Entomology]] |volume=52 |issue=1 |year=2007 |pages=151–170 |doi=10.1146/annurev.ento.52.110405.091326 |pmid=16872257 |url=https://www.researchgate.net/publication/6914719 }}</ref><ref>{{cite journal |last=Arthur |first=Wallace |year=2002 |title=The interaction between developmental bias and natural selection from centipede segmentation to a general hypothesis |journal=[[Heredity (journal)|Heredity]] |volume=89 |issue=4 |pages=239–246 |pmid=12242638 |doi=10.1038/sj.hdy.6800139 |doi-access=free }}</ref><ref>{{cite journal |last1=Arthur |first1=Wallace |last2=Chapman |first2=Ariel D. |year=2005 |title=The centipede ''Strigamia maritima'': what it can tell us about development and evolution of segmentation |journal=[[BioEssays]] |volume=27 |issue=6 |pages=653–660 |pmid=15892117 |doi=10.1002/bies.20234}}</ref><ref>{{cite book |last=Minelli |first=Alessandro |editor1-last=Ayala |editor1-first=Francisco J. |editor2-last=Arp |editor2-first=Robert |title=Contemporary Debates in Philosophy of Biology |year=2009 |publisher=John Wiley and Sons |isbn=978-1-4051-5999-9 |pages=213–226 |chapter-url=https://books.google.com/books?id=4p6sGSjdVxUC&pg=PA218 |chapter=Evolutionary developmental biology does not offer a significant challenge to the neo-Darwinian paradigm}}</ref>

Centipedes are predominantly [[generalist and specialist species|generalist]] predators, which means they are adapted to eat a broad range of prey.{{sfn|Lewis|2007|p=168}} Common prey items include [[Lumbricidae|lumbricid]] earthworms, [[diptera]]n fly larvae, [[collembola]]ns, and other centipedes.<ref name="Klarner Winkelmann Krashevska Maraun 2017 p=e0180915">{{cite journal |last1=Klarner |first1=Bernhard |last2=Winkelmann |first2=Helge |last3=Krashevska |first3=Valentyna |last4=Maraun |first4=Mark |last5=Widyastuti |first5=Rahayu |last6=Scheu |first6=Stefan |title=Trophic niches, diversity and community composition of invertebrate top predators (Chilopoda) as affected by conversion of tropical lowland rainforest in Sumatra (Indonesia) |journal=PLOS ONE |volume=12 |issue=8 |date=2017-08-01 |issn=1932-6203 |doi=10.1371/journal.pone.0180915 |page=e0180915|pmid=28763453 |pmc=5538669 |bibcode=2017PLoSO..1280915K |doi-access=free }}</ref> They are carnivorous; study of gut contents suggests that plant material is an unimportant part of their diets, although they eat vegetable matter when starved during laboratory experiments.{{sfn|Lewis|2007|p=168}}

Among Geophilomorphs, the secretions of ''Geophilus vittatus'' are sticky and odorous, and contain hydrogen cyanide.<ref name="Jones Conner Meinwald Eisner 1976 pp. 421–429">{{cite journal |last1=Jones |first1=Tappey H. |last2=Conner |first2=William E. |last3=Meinwald |first3=Jerrold |last4=Eisner |first4=Hans E. |last5=Eisner |first5=Thomas |title=Benzoyl cyanide and mandelonitrile in the cyanogenetic secretion of a centipede |journal=Journal of Chemical Ecology |volume=2 |issue=4 |year=1976 |issn=0098-0331 |doi=10.1007/bf00988807 |pages=421–429|bibcode=1976JCEco...2..421J |s2cid=20051462 }}</ref>

AsAccording ofto the 2019 [[IUCN Red List]], there are twoone [[Vulnerable species|vulnerable]], and onesix [[endangered species|endangered]], and three [[Critically Endangered|critically endangered]] species of centipede.<ref>{{Cite web |date=28 July 2024 |title=IUCN 2024 |url=https://www.iucnredlist.org/search?taxonomies=100034&searchType=species |website=The IUCN Red List of Threatened Species}}</ref> For example, the [[Scolopendra abnormis|Serpent Island centipede]] (''Scolopendra abnormis),'' is vulnerable, and [[Nothogeophilus turki|Turk's earth centipede]] ''(Nothogeophilus turki),'' and the [[Seychellonema gerlachi|Seychelles long-legged centipede]] (''Seychellonema gerlachi)'', the first two of which are vulnerable and the lastboth endangered.<ref>Pearce-Kelly, P. 1996. [https://www.iucnredlist.org/species/20042/9138315 ''Scolopendra abnormis''. ''The IUCN Red List of Threatened Species'' 1996]: e.T20042A9138315. {{doi|10.2305/IUCN.UK.1996.RLTS.T20042A9138315.en}}. Accessed on 10 January 2023.</ref><ref>Macadam, C. 2022. [https://www.iucnredlist.org/species/123669218/123674269 ''Nothogeophilus turki''. ''The IUCN Red List of Threatened Species'' 2022]: e.T123669218A123674269. {{doi|10.2305/IUCN.UK.2022-1.RLTS.T123669218A123674269.en}}. Accessed on 10 January 2023.</ref><ref>Gerlach, J. 2014. [https://www.iucnredlist.org/species/201495/15280805 ''Seychellonema gerlachi''. ''The IUCN Red List of Threatened Species'' 2014]: e.T201495A15280805. {{doi|10.2305/IUCN.UK.2014-1.RLTS.T201495A15280805.en}}. Accessed on 10 January 2023.</ref>

The [[fossil record]] of centipedes extends back to {{Ma|430}}, during the [[Late Silurian]] (''[[Crussolum]]''),<ref>{{cite journal |last=Shear |first=W. A. |year=1992 |title=Early life on land |journal=[[American Scientist]] |volume=80 |issue=5 |pages=444–456|bibcode=1992AmSci..80..444G }}</ref><ref>{{cite journal |last1=Jeram |first1=Andrew J. |last2=Selden |first2=Paul A. |last3=Edwards |first3=Dianne |title=Land Animals in the Silurian: Arachnids and Myriapods from Shropshire, England |journal=[[Science (journal)|Science]] |date=2 November 1990 |volume=250 |issue=4981 |pages=658–661 |doi=10.1126/science.250.4981.658 |pmid=17810866 |bibcode=1990Sci...250..658J |url=https://horseshoecrab.org/research/sites/default/files/P.Shelden%201990.pdf}}</ref> though they are rare throughout the [[Paleozoic]].<ref name="Wilson 2003"/> The [[Devonian]] [[Panther Mountain Formation]] contains two species of centipede,. oneOne is a species of the scutigeromorph ''Crussolum'',. otherThe oneother is ''[[Devonobius]]'', which is included in anthe extinct group Devonobiomorpha.<ref name=":3">{{Cite journal |last1=Shear |first1=William A. |last2=Jeram |first2=Andrew J. |last3=Selden |first3=Paul |date=1998 |title=Centiped legs (Arthropoda, Chilopoda, Scutigeromorpha) from the Silurian and Devonian of Britain and the Devonian of North America. American Museum novitates ; no. 3231 |url=http://hdl.handle.net/2246/3370 |journal=New York, NY : American Museum of Natural HistoryNovitates |issue=3231|hdl=2246/3370}}</ref><ref>{{Cite webjournal |last1=Bonamo |first1=P. M. |last2=Shear |first2=William A. |date=1988 |others=American Museum of Natural History Library |title=Devonobiomorpha, a new order of centipeds (Chilopoda) from the Middle Devonian of Gilboa, New York State, USA, and the phylogeny of centiped orders. |journal=American Museum novitates ; no.Novitates |issue=2927 |url=https://www.biodiversitylibrary.org/bibliography/93435 |access-date= |websitevia=Biodiversity Heritage Library}}</ref> Another Devonian site, the [[Rhynie chert]], also have record ofbears ''Crussolum'' fossils,<ref name=":3" /> and possible scutigeromorph head material. ''[[Rhyniognatha]]'' is known, which was once consideredthought asto be the oldest insect fossil, is also found in the Rhynie Chert.<ref>{{Cite journal |last1=Haug |first1=Carolin |last2=Haug |first2=Joachim T. |date=2017-05-30 |title=The presumed oldest flying insect: more likely a myriapod? |journal=PeerJ |volume=5 |pages=e3402 |doi=10.7717/peerj.3402 |doi-access=free |pmid=28584727 |pmc=5452959 |issn=2167-8359}}</ref> Three species, one scutigeromorph (''[[Latzelia]]'') and two scolopendromorphs (''[[Mazoscolopendra]]'' and the poorly known ''[[Palenarthrus]]''), have been described from the [[Mazon Creek fossil beds]], which are [[Carboniferous]], 309–307 mya.<ref name="Shear">{{cite book |editor=Minelli, Alessandro |year=1990 |title=Proceedings of the 7th International Congress of Myriapodology |publisher=[[Brill Publishers]] |isbn=978-90-04-08972-3 |last1=Shear |first1=William A. |last2=Bonamo |first2=Patricia M. |chapter=Fossil centipedes from the Devonian of New York State, U.S.A. |pages=89–96 |chapter-url=https://books.google.com/books?id=BJzFnCunVxsC&pg=PA89}}</ref> More species appear in the [[Mesozoic]], including scolopendromorphs and scutigeromorphs in the [[Cretaceous]].<ref name="Wilson 2003">{{cite journal |author=Heather M. Wilson |year=2003 |title=A new scolopendromorph centipede (Myriapoda: Chilopoda) from the Lower Cretaceous (Aptian) of Brazil |url=https://onlinelibrary.wiley.com/doi/pdf/10.1111/1475-4983.00188|journal=[[Journal of Paleontology]] |volume=77 |issue=1 |pages=73–77 |jstor=4094718 |doi=10.1666/0022-3360(2003)077<0073:ANSCMC>2.0.CO;2|s2cid=130297755 }}</ref><ref name="Wilson 2001 pp. 489–495">{{cite journal | last=Wilson | first=Heather M. | title=First Mesozoic Scutigeromorph Centipede, from the Lower Cretaceous of Brazil | journal=Palaeontology | publisher=Wiley | volume=44 | issue=3 | year=2001 | issn=0031-0239 | doi=10.1111/1475-4983.00188 | pages=489–495| bibcode=2001Palgy..44..489W | doi-access=free }}</ref>

* [http://chilobase.biologia.unipd.it/ Chilobase, a web resource for Chilopoda taxonomy]. {{Webarchive|url=https://web.archive.org/web/20171106052057/http://chilobase.biologia.unipd.it/ |date=2017-11-06 }}.

* [https://web.archive.org/web/20060824064342/http://www.atshq.org/articles/centipedes.html Debunking of some centipede myths], – American Tarantula Society

* [http://tolweb.org/tree?group=Chilopoda&contgroup=Arthropoda Chilopoda]. {{Webarchive|url=https://web.archive.org/web/20090416065704/http://tolweb.org/tree?group=Chilopoda&contgroup=Arthropoda |date=2009-04-16 }},. [[Tree of Life Web Project]].