# Symphyla > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Symphyla > Markdown URL: https://mediated.wiki/source/Symphyla.md > Source: https://en.wikipedia.org/wiki/Symphyla > Source revision: 1354767445 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Class of many-legged arthropods}} {{Distinguish|Symphyta}} {{Automatic taxobox | fossil_range = {{Fossil range|99|0}}Mid [Cretaceous](/source/Cretaceous) to [Present](/source/Holocene) | image = Scutigerella 116012425.jpg | image_caption = ''[Scutigerella](/source/Scutigerella)'' sp. (Scutigerellidae) | image2 = Garden Centipede-Symphyla sp. (8578774949).jpg | image2_caption = Scolopendrellid symphylan (Scolopendrellidae) | taxon = Symphyla | authority = [Ryder](/source/John_A._Ryder), 1880 | subdivision_ranks = Families | subdivision = [Scutigerellidae](/source/Scutigerellidae)
[Scolopendrellidae](/source/Scolopendrellidae) }} '''Symphylans''', also known as '''garden centipedes''' or '''pseudocentipedes''', are soil-dwelling [arthropods](/source/arthropods) of the [class](/source/class_(biology)) '''Symphyla''' in the subphylum [Myriapoda](/source/Myriapoda). Symphylans resemble [centipede](/source/centipede)s but are very small, non-venomous, and [may or may not form a clade with centipedes](/source/Myriapoda).{{cite book |author=C. Gillott |year=2005 |title=Entomology, 3rd Edition |publisher=[Springer Verlag](/source/Springer_Verlag) |isbn=978-1-4020-3182-3}} More than 200 species are known worldwide.{{Cite web |title=ITIS - Report: Symphyla |url=https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=154408#null |access-date=2024-02-28 |website=www.itis.gov}} Symphyla are primarily [herbivore](/source/herbivore)s and [detritus](/source/detritus) feeders living deep in the soil, under stones, in decaying wood, and in other moist places. They are rapid runners, can move quickly through the pores between soil particles, and are typically found from the surface down to a depth of about {{convert|50|cm|in|sigfig=1}}. They [consume decaying vegetation](/source/detritivore) but can do considerable harm in an [agricultural](/source/Agriculture) setting by consuming seeds, roots, and root hairs in cultivated soil. For example, the garden symphylan, ''[Scutigerella immaculata](/source/Scutigerella_immaculata)'' can be a pest of crops. A species of ''[Hanseniella](/source/Hanseniella_(myriapod))'' has been recorded as a pest of [sugar cane](/source/sugar_cane) and [pineapple](/source/pineapple)s in [Queensland](/source/Queensland).{{cite journal |author=H. Boyle |year=1981 |title=Symphyla control in young plant cane |journal=Cane Growers' Quarterly Bulletin |volume=44 |pages=115–116}}{{cite journal |author=D. A. H. Murray & D. Smith |year=1983 |title=Effect of Symphyla, ''Hanseniella'' sp., on establishment of pineappes in south-east Queensland |journal=Queensland Journal of Agricultural Science |volume=40 |pages=121–123}} A few species are found in trees{{cite journal |author=J. Adis & U. Scheller |year=1984 |title=On the natural history and ecology of ''Hanseniella arborea'' (Myriapoda, Symphyla, Scutigerellidae), a migrating symphylan from an Amazonian black-water inundation forest |journal=Pedobiologia |volume=27 |pages=35–41 |doi=10.1016/S0031-4056(23)05818-3 |s2cid=89444581 |doi-access=free}}{{cite journal |author=S. Clark & P. Greenslade |year=1996 |title=Review of Tasmanian ''Hanseniella'' Bagnall (Symphyla: Scutigerellidae) |journal=Invertebrate Taxonomy |volume=10 |issue=1 |pages=189–212 |doi=10.1071/IT9960189}} and in caves.{{cite journal |author=Eberhard, S.M. & Spate |year=1995 |title=Cave Invertebrate Survey; toward an atlas of NSW Cave Fauna |journal=A Report Prepared Under NSW Heritage Assistance Program NEP |volume=94 |pages=765}} A species of ''Symphylella'' has been shown to be predominantly predatory,{{cite journal |author=D. E. Walter, J. C. Moore & S. Loring |year=1989 |title=''Symphylella'' sp. (Symphyla: Scolopendrellidae predators of arthropods and nematodes in grassland soils |journal=Pedobiologia |volume=33 |issue=2 |pages=113–116|doi=10.1016/S0031-4056(24)00190-2 |bibcode=1989Pedob..33..113W }} and some species are [saprophagous](/source/saprophagous). == Description == [[File:Scutigerella 63392733.jpg|thumb|Individuals of [''Scutigerella'' sp](/source/Scutigerella). (left, top) and [Scolopendrellidae](/source/Scolopendrellidae) (right, bottom), showing their small size|left]] Symphyla are small, [cryptic](/source/crypsis) myriapods without eyes and without [pigment](/source/pigment).{{cite web |url=http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/afd/taxa/SYMPHYLA |title=Class: Symphyla |work=[Australian Faunal Directory](/source/Australian_Faunal_Directory) |author=Penny Greenslade |date=2002-03-31 |publisher=[Australian National University](/source/Australian_National_University) |url-status=dead |archive-url=https://web.archive.org/web/20150924052402/http://www.environment.gov.au/biodiversity/abrs/online-resources/fauna/afd/taxa/SYMPHYLA |archive-date=2015-09-24}} The body is soft and generally {{convert|2|to|10|mm|in|sigfig=1}} long, divided into two body regions: head and trunk. An exceptional size is reached in ''[Hanseniella magna](/source/Hanseniella_magna)'', which attains lengths of 12–13 mm (0.5 in). Scheller, U. (1996) https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1440-6055.1996.tb01391.x The head has long, segmented [antennae](/source/Antenna_(biology)), a postantennal organ, three pairs of [mouthparts](/source/Arthropod_mouthparts): [mandibles](/source/Mandible_(arthropod)), the long first maxillae, and the second pair of maxillae which are fused to form the lower lip or labium of the mouth. The antennae serve as sense organs. Disc-like [organs of Tömösváry](/source/organ_of_T%C3%B6m%C3%B6sv%C3%A1ry), which probably sense vibrations, are attached to the base of the antennae, as they are in centipedes.{{cite book |author= Barnes, Robert D. |year=1982 |title= Invertebrate Zoology |publisher= Holt-Saunders International |location= Philadelphia, PA|pages= 817–818|isbn= 978-0-03-056747-6}} The trunk comprises 14 segments, which are covered by microhairs on the lateral and ventral integument and by a various number of dorsal [tergal](/source/Tergum) plates, from 15 in ''[Scutigerella](/source/Scutigerella)'' and [''Hanseniella''](/source/Hanseniella_(myriapod)), and up till 24 in ''[Ribautiella](/source/Ribautiella)'', increasing the flexibility of the body. [Legs](/source/arthropod_leg) are found on the first 12 segments. The 13th segment, which is fused with the 12th segment, bears a pair of [spinneret](/source/spinneret)s that resemble [cerci](/source/cercus), and the 14th segment has a pair of long sensory hairs ([trichobothria](/source/trichobothria)). Around the anal opening there is a small [telson](/source/telson).[https://books.google.no/books?id=x7vtCAAAQBAJ&pg=PA229&dq=Symphyla+spinnerets+paired+spin+glands+telson&hl=no&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwiH6OXgv4mJAxXwFRAIHR0fNEsQ6AF6BAgHEAI#v=onepage&q=Symphyla%20spinnerets%20paired%20spin%20glands%20telson&f=false Multicellular Animals: Volume II: The Phylogenetic System of the Metazoa][https://books.google.no/books?id=YLxJETTBCSsC&pg=PA182&dq=symphylans+twelve+leg-less+tergal+plates+24&hl=no&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwiBlJvZuYmJAxUFExAIHXfHK8MQ6AF6BAgKEAI#v=onepage&q=symphylans%20twelve%20leg-less%20tergal%20plates%2024&f=false The Invertebrates: A Synthesis][https://books.google.no/books?id=Hd4OEDo4gbwC&pg=PA367&dq=Symphyla+segments+vestigial+separated&hl=no&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwiK5u_vyoyJAxU6ExAIHXVFLZgQ6AF6BAgEEAI#v=onepage&q=Symphyla%20segments%20vestigial%20separated&f=false Biology of Arthropoda][https://books.google.no/books?id=sbBG4-G7arQC&pg=PA17&dq=symphyla+microhairs&hl=no&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwiOnYGay4yJAxVgLRAIHSjYBhgQ6AF6BAgKEAI#v=onepage&q=symphyla%20microhairs&f=false Intestinal Microorganisms of Termites and Other Invertebrates] Symphylans have been reported as living up to four years, and [moult](/source/Ecdysis) throughout their life. Immature individuals have six or seven pairs of legs on hatching, but they add an additional pair at each [moult](/source/ecdysis) until the adult [instar](/source/instar), which usually has twelve pairs of legs.{{cite web |title=Garden Symphylans |url=http://mint.ippc.orst.edu/symphid.htm |url-status=dead |archive-url=https://web.archive.org/web/20070803172418/http://mint.ippc.orst.edu/symphid.htm |archive-date=2007-08-03 |access-date=2007-07-02 |work=Integrated Pest Management on Peppermint-IPMP3.0 |publisher=[Oregon State University](/source/Oregon_State_University)}}{{cite web |title=Symphylans |url=https://encyclopediaofarkansas.net/entries/symphylans-14863/ |access-date=2021-05-29 |work=Entry: Symphylans |publisher=[Encyclopedia of Arkansas](/source/Encyclopedia_of_Arkansas)}} This mode of development is known as [hemianamorphosis](/source/Anamorphosis_(biology)).{{cite journal |last1=Fusco |first1=Giuseppe |date=December 2005 |title=Trunk segment numbers and sequential segmentation in myriapods. |url=https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1525-142X.2005.05064.x |journal=Evolution & Development |volume=7 |issue=6 |pages=608–617 |doi=10.1111/j.1525-142X.2005.05064.x |pmid=16336414 |s2cid=21401688 |access-date=25 August 2020|url-access=subscription }} Although most adult symphylans have twelve leg pairs, the first pair is absent or vestigial in some species (e.g., those in the genus ''[Symphylella](/source/Scolopendrellidae)''), so adults in some species have only eleven leg pairs.{{Cite book |last1=Szucsich |first1=Nikola |title=The Myriapoda. Volume 1 |last2=Scheller |first2=Ulf |publisher=Brill |year=2011 |isbn=978-90-04-18826-6 |editor-last=Minelli |editor-first=Alessandro |location=Leiden |pages=445–466 |chapter=Symphyla |oclc=812207443}}{{Citation |last1=Minelli |first1=Alessandro |title=Myriapods |date=2013-01-01 |url=https://www.sciencedirect.com/science/article/pii/B9780123847195002082 |pages=421–432 |editor-last=Levin |editor-first=Simon A |access-date=2022-02-28 |place=Waltham |publisher=Academic Press |language=en |doi=10.1016/b978-0-12-384719-5.00208-2 |isbn=978-0-12-384720-1 |last2=Golovatch |first2=Sergei I. |encyclopedia=Encyclopedia of Biodiversity (Second Edition)|url-access=subscription }} The species with 12 pairs are the only myriapods with walking legs on the first body segment, as the first pair of legs are modified into [forcipule](/source/forcipule)s in centipedes, in pauropods this segment is a reduced [collum](/source/Collum_(millipede)) which bears ventrally a pair of small papillae, and in millipedes this segment is a collum without any appendages at all.[https://muse.jhu.edu/pub/255/oa_monograph/chapter/2413845 Textbook of Arthropod Anatomy] Symphylans have several features linking them to early insects, such as a labium (fused second maxillae), an identical number of head segments, and certain features of their legs. Each pair of legs is associated with an eversible structure called a "coxal sac", which helps the animal absorb moisture, and a small stylus that may be sensory in function. Similar structures are found in the most primitive insects.thumb|left|Life stages of symphylans: eggs, juvenile, and adult ''Scutigerella immaculata'' Symphylans breathe through a pair of [spiracle](/source/Spiracle_(arthropods))s on the sides of their head and are the only arthropods with spiracle openings on the head.[https://books.google.com/books?id=8ZnEDAAAQBAJ&dq=Symphylans+are+the+only+group+respiratory+openings+on+the+head&pg=PA206 BIOLOGICAL SCIENCE FUNDAMENTALS AND SYSTEMATICS - Volum III] These are connected to a system of [tracheae](/source/invertebrate_trachea) that branch through the head and the first three segments of the body only. The genital openings are located on the fourth body segment, but the animals do not copulate. Instead, the male deposits 150 to 450 packages of sperm, or [spermatophore](/source/spermatophore)s, on small stalks. The female then picks these up in her mouth, which contains special pouches for storing the sperm. She then lays her eggs, and attaches them to the sides of crevices or to moss or lichen with her mouth, smearing the sperm over them as she does so. The eggs are laid in groups of eight to twelve. The [spinneret](/source/spinneret)s produce secretions that turn into a silk-like thread.{{Cite book |title=Arthropod Anatomy |chapter=X: The Symphyla |jstor=10.7591/j.ctvn1tb6g.14 |chapter-url=https://www.jstor.org/stable/pdf/10.7591/j.ctvn1tb6g.14.pdf }} One fossil species, ''[Symphylella patrickmuelleri](/source/Symphylella_patrickmuelleri),'' was found preserved in [Burmese amber](/source/Burmese_amber) releasing long threads of silk.{{Cite journal |last1=Moritz |first1=Leif |last2=Wesener |first2=Thomas |date=2018-04-01 |title=Symphylella patrickmuelleri sp. nov. (Myriapoda: Symphyla): The oldest known Symphyla and first fossil record of Scolopendrellidae from Cretaceous Burmese amber |url=https://www.sciencedirect.com/science/article/pii/S0195667117304068 |journal=Cretaceous Research |language=en |volume=84 |pages=258–263 |doi=10.1016/j.cretres.2017.11.018 |bibcode=2018CrRes..84..258M |issn=0195-6671|url-access=subscription }} The silk plays a role in reproduction: the male deposits up to 450 spermatophores on stalks of silk.{{Cite web |title=Symphylans |url=https://encyclopediaofarkansas.net/entries/symphylans-14863/ |access-date=2023-05-02 |website=Encyclopedia of Arkansas |language=en-US |quote=For reproduction, males do not copulate with the female. Rather, they deposit 150 to 450 sperm packets (spermatophores) on top of short stalks of silk on the ground.}} Symphylans have also been reported releasing silk as a defense{{Citation |last=Schulze |first=L. |title=Structure, composition and properties of spun products |date=Jan 1975 |url=https://journals.co.za/doi/pdf/10.10520/AJA0000012_281}} and to suspend themselves in the air. ==Fossil record and evolution== The symphylan fossil record is poorly known, with only five species recorded, all placed in living genera. The oldest records of both families are found in Burmese amber from the middle [Cretaceous](/source/Cretaceous), approximately 99 million years ago. As a result, both families are thought to have diverged before the end of the Mesozoic Era.{{cite journal|last1=Moritz|first1=Leif|last2=Wesener|first2=Thomas|title=''Symphylella patrickmuelleri'' sp. nov. (Myriapoda: Symphyla): The oldest known Symphyla and first fossil record of Scolopendrellidae from Cretaceous Burmese amber|journal=Cretaceous Research|volume=84|pages=258–263|date=2017|doi=10.1016/j.cretres.2017.11.018|bibcode=2018CrRes..84..258M }}{{cite book|first=Alessandro|last= Minelli|title=Treatise on Zoology - Anatomy, Taxonomy, Biology. The Myriapoda|url=https://books.google.com/books?id=IrWcS9fut1oC&pg=PA459|year=2011|publisher=BRILL|isbn=978-90-04-15611-1|page=459}}{{Cite journal|last1=Wesener|first1=Thomas|last2=Moritz|first2=Leif|date=2018-12-17|title=Checklist of the Myriapoda in Cretaceous Burmese amber and a correction of the Myriapoda identified by Zhang (2017)|journal=Check List|language=en|volume=14|issue=6|pages=1131–1140|doi=10.15560/14.6.1131|issn=1809-127X|doi-access=free|s2cid=92289899 }} Despite their common name, morphological studies commonly place symphylans as more closely related to [millipede](/source/millipede)s and [pauropod](/source/pauropod)s than the [centipede](/source/centipede)s, in the clade [Progoneata](/source/Progoneata).{{cite journal|last=Shear|first=William A.|author2=Edgecombe, Gregory D. |title=The geological record and phylogeny of the Myriapoda|journal=Arthropod Structure & Development|date=2010|volume=39|issue=2–3|pages=174–190|doi=10.1016/j.asd.2009.11.002|pmid=19944188|bibcode=2010ArtSD..39..174S }}{{cite journal|last=Gai|first=Yonghua|author2=Song, Daxiang |author3=Sun, Hongying |author4=Yang, Qun |author5= Zhou, Kaiya |title=The complete mitochondrial genome of ''Symphylella'' sp. (Myriapoda: Symphyla): Extensive gene order rearrangement and evidence in favor of Progoneata|journal=Molecular Phylogenetics and Evolution|date=2008|volume=49|issue=2|pages=574–585|doi=10.1016/j.ympev.2008.08.010|url=https://www.researchgate.net/publication/23248321 |pmid=18782622|bibcode=2008MolPE..49..574G }} [Molecular studies](/source/Molecular_phylogenetics) have shown conflicting results, with some supporting the Progoneata clade, others aligning symphylans with centipedes or other arthropods, although some are weakly supported.{{cite journal|last=Regier|first=Jerome C.|author2=Wilson, Heather M. |author3=Shultz, Jeffrey W. |title=Phylogenetic analysis of Myriapoda using three nuclear protein-coding genes|journal=Molecular Phylogenetics and Evolution|date=2005|volume=34|issue=1|pages=147–158|doi=10.1016/j.ympev.2004.09.005|pmid=15579388|bibcode=2005MolPE..34..147R }} The clade is believed to be [monophyletic](/source/monophyletic).{{Cite journal |last1=Jin |first1=Ya-Li |last2=Godeiro |first2=Nerivania Nunes |last3=Bu |first3=Yun |date=2023-05-04 |title=Description of the first species of Scutigerella (Symphyla, Scutigerellidae) from China, with mitogenomic and genetic divergence analysis |url=https://zookeys.pensoft.net/article/99686/ |journal=ZooKeys |language=en |issue=1157 |pages=145–161 |doi=10.3897/zookeys.1157.99686 |pmid=37215163 |pmc=10193434 |issn=1313-2970 |doi-access=free |bibcode=2023ZooK.1157..145J }} ==References== {{Reflist|32em}} ===Further reading=== *{{cite book |author=C. A. Edwards |year=1990 |chapter=Symphyla |pages=891–910 |editor=Daniel L. Dindal |title=Soil Biology Guide |publisher=New York: Wiley |isbn=978-0-471-04551-9}} *{{cite journal |author=U. Scheller |year=1961 |title=A review of the Australian Symphyla (Myriapoda) |journal=Australian Journal of Zoology |volume=9 |issue=1 |pages=140–171 |doi=10.1071/ZO9610140}} *{{cite book |author=U. Scheller |year=1982 |chapter=Symphyla |pages=[https://archive.org/details/synopsisclassifi02park/page/688 688–689] |editor=Sybil P. Parker |title=Synopsis and Classification of Living Organisms |chapter-url=https://archive.org/details/synopsisclassifi02park |chapter-url-access=registration |publisher=New York: McGraw-Hill |isbn=978-0-07-079031-5}} *{{cite journal |author=R. J. Tillyard |year=1930 |title=The evolution of the class Insecta |journal=Papers and Proceedings of the Royal Society of Tasmania |volume=1930 |pages=1–89|doi=10.26749/IXAJ2535 |url=https://figshare.com/articles/journal_contribution/The_evolution_of_the_class_Insecta/24604155/1/files/43233978.pdf }} ==External links== {{Commons category}} {{Portal|Arthropods}} * {{Wikispecies-inline|Symphyla}} {{Arthropods}} {{Taxonbar|from=Q244147}} {{Authority control}} Category:Symphyla Category:Arthropod classes Category:Taxa named by John A. Ryder --- Adapted from the Wikipedia article [Symphyla](https://en.wikipedia.org/wiki/Symphyla) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Symphyla?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.