Mandibulata

{{Short description|Clade of arthropods}} {{Automatic taxobox | fossil_range = {{fossil range|Cambrian Stage 3|Recent}} | image = Mandibulata specimens – macro photography collage.png | image_caption = Mandibulata specimens showcasing the defining feature of the clade: the mandible. Pictured left to right, top to bottom: littoral tiger beetle, barnacles, European lobster, ''Scolopendra'' centipede, Dungeness crab, bull ant. | image2 = Odaraia.png | image2_caption = Life restoration of ''Odaraia'', an early mandibulate belonging to Hymenocarina with mandibles present near the mouth | taxon = Mandibulata | authority = de Clairville, 1798 | subdivision_ranks = Subdivisions | subdivision = *Pancrustacea {{small|(including hexapods)}} *Myriapoda *†Euthycarcinoidea *†Hymenocarina *†Fuxianhuiida *†Phosphatocopina {{collapse top|title=''incertae sedis'' (including possible stem-group mandibulates)}} *†''Acheronauta''? *†''Aquilonifer'' *†Bradoriida? *†Cambropachycopidae? *†''Cambropodus''? *†''Captopodus''? *†''Cascolus''? *†''Martinssonia''? *†''Papiliomaris''? *†''Parioscorpio''? *†''Rhyniognatha''? *†Skaracarida? *†''Tanazios''? *†Marrellomorpha? *†Thylacocephala? *†Oelandocarididae? *†''Musacaris''? {{collapse bottom}} }}

The clade '''Mandibulata''' constitutes one of the two major living subdivisions of the phylum Arthropoda,<ref>{{Cite web |title=Mandibulata |url=https://www.ncbi.nlm.nih.gov/datasets/taxonomy/197563/ |access-date=2026-03-23 |website=NCBI |language=en}}</ref> alongside Chelicerata. Mandibulates include the myriapods (centipedes and millipedes, among others), and the pancrustaceans (including all true insects). The name "Mandibulata" refers to the mandibles, a modified pair of limbs used in food processing, the presence of which are characteristic of most members of the group.

== Characteristics == Mandibulates are characterized by a head tagma that has antennae and three feeding appendages that make up the mandible.<ref>{{Cite book |last=Chipman |first=Ariel D. |url=https://academic.oup.com/book/56289/chapter-abstract/445244059?redirectedFrom=fulltext&login=false |title=Arthropoda II: Mandibulata |publisher=OUP Oxford |year=2024 |isbn=978-0192893598 |pages=137–146}}</ref>

== Taxonomy == The name "Mandibulata" was originally used for a subgroup of insects by Joseph Philippe de Clairville in 1798.<ref>{{Cite book |last=Schellenberg |first=Johann Rudolf |url=https://www.biodiversitylibrary.org/bibliography/15822 |title=Helvetische Entomologie, oder, Verzeichniss der schweizerischen Insekten nach einer neuen Methode geordnet : mit Beschreibungen und Abbildungen |last2=Joseph Philippe de |first2=Clairville |last3= |first3= |date=1798 |publisher=Bei Orell, Füssli und Compagnie |location=Zürich}}</ref> In the 1930s, Robert Evans Snodgrass used the name to encompass myriapods, hexapods and crustaceans, which he considered to be united by a number of morphological similarities, including but not limited to the presence of mandibles.<ref>SNODGRASS, R. E. 1938. Evolution of the Annelida, Onychophora, and Arthropoda. ''Smithsonian Miscellaneous Collections'' '''97:''' 1–159.</ref> This proposal was contested by some other 20th century scholars, who considered mandibles the result of convergent evolution,<ref>Edgecombe, G.D. ∙ Richter, S. ∙ Wilson, G.D.F. [https://journals.co.za/doi/pdf/10.10520/EJC84510 The mandibular gnathal edges: Homologous structures throughout Mandibulata?] ''Afr. Invertebr.'' 2003; '''44''':115-135</ref> though the monophyly of Mandibulata is now widely accepted based on genetic evidence.<ref>{{Cite journal |last=Giribet |first=Gonzalo |last2=Edgecombe |first2=Gregory D. |date=June 17, 2019 |title=The Phylogeny and Evolutionary History of Arthropods |url=https://doi.org/10.1016/j.cub.2019.04.057 |journal=Current Biology |volume=29 |issue=12 |pages=R592–R602 |doi=10.1016/j.cub.2019.04.057 |issn=0960-9822|url-access=subscription }}</ref>

=== Phylogeny === Some studies suggest that Artiopoda, the broader group that contains trilobites and their extinct relatives, is more closely related to Mandibulata than to Chelicerata, and that artiopods and mandibulates are united by their shared presence of antennae, which these authors propose was a shared common ancestral trait. Consequently, the proposed clade containing both Artiopoda and Mandibulata is named Antennulata.<ref>{{Cite journal |last=Aria |first=Cédric |date=26 April 2022 |title=The origin and early evolution of arthropods |url=https://onlinelibrary.wiley.com/doi/10.1111/brv.12864 |journal=Biological Reviews |language=en |volume=97 |issue=5 |pages=1786–1809 |doi=10.1111/brv.12864 |issn=1464-7931 |url-access=subscription}}</ref> This grouping may also contain other extinct arthropod groups like Marrellomorpha.<ref name=":1">{{cite journal |last1=Liu |first1=Yao |last2=Zeng |first2=Han |last3=Zhao |first3=Fangchen |last4=Zhu |first4=Yuyan |last5=Li |first5=Yimeng |last6=Yin |first6=Zongjun |last7=Zhu |first7=Maoyan |date=31 May 2025 |title=A tiny Cambrian stem-mandibulate reveals independent evolution of limb tagmatization and specialization in early euarthropods |journal=Scientific Reports |volume=15 |issue=1 |doi=10.1038/s41598-025-03544-0 |pmc=12126567}}</ref>

The mandibulates are divided between the extant groups Myriapoda (millipedes and centipedes, among others) and Pancrustacea (including crustaceans and hexapods, the latter group containing insects). Molecular phylogenetic studies suggest that the living arthropods are related as shown in the cladogram below. Crustaceans do not form a monophyletic group as insects and other hexapods have evolved from within them.<ref name="Regier" /><ref name="vonJennWillDell11" /><ref name="RotaStabelli11" />

Some extinct groups have been placed in Mandibulata, including Hymenocarina,<ref name=":8">{{Cite journal |last=Izquierdo-López |first=Alejandro |last2=Caron |first2=Jean-Bernard |date=August 2024 |title=The Cambrian Odaraia alata and the colonization of nektonic suspension-feeding niches by early mandibulates |url=https://royalsocietypublishing.org/doi/10.1098/rspb.2024.0622 |journal=Proceedings of the Royal Society B: Biological Sciences |language=en |volume=291 |issue=2027 |doi=10.1098/rspb.2024.0622 |issn=1471-2954 |pmc=11463219 |pmid=39043240}}</ref> Euthycarcinoidea,<ref>{{cite journal |last1=Edgecombe |first1=Gregory D. |last2=Strullu-Derrien |first2=Christine |last3=Góral |first3=Tomasz |last4=Hetherington |first4=Alexander J. |last5=Thompson |first5=Christine |last6=Koch |first6=Marcus |year=2020 |title=Aquatic stem group myriapods close a gap between molecular divergence dates and terrestrial fossil record |journal=Proceedings of the National Academy of Sciences |volume=117 |issue=16 |pages=8966–8972 |doi=10.1073/pnas.1920733117 |pmc=7183169 |pmid=32253305 |s2cid=215408474 |doi-access=free}}</ref> and Fuxianhuiida.<ref>{{Cite journal |last=Aria |first=Cédric |last2=Zhao |first2=Fangchen |last3=Zhu |first3=Maoyan |date=September 2021 |title=Fuxianhuiids are mandibulates and share affinities with total-group Myriapoda |url=https://www.lyellcollection.org/doi/10.1144/jgs2020-246 |journal=Journal of the Geological Society |volume=178 |issue=5 |doi=10.1144/jgs2020-246 |issn=0016-7649|url-access=subscription }}</ref>

Cladogram after Liu et al, 2026:<ref>{{Cite journal |last=Liu|first=Cong|last2=Pates|first2=Stephen|last3=Zhang|first3=Mingjing|last4=Wu|first4=Yu|last5=Ma|first5=Jiaxin|last6=Fu|first6=Dongjing|last7=Zhang|first7=Xingliang|date=2026-03-21|title=3D morphology of the Cambrian bivalved arthropod Sunella informs about head segmentation, arthrodization, and arthropodization|url=https://www.nature.com/articles/s42003-026-09909-z|journal=Communications Biology|language=en|doi=10.1038/s42003-026-09909-z|issn=2399-3642|doi-access=free}}</ref>{{clade|{{clade |1={{extinct}} "Lobopodia" 80 px 90 px 50 px (paraphyletic, ancestral to tardigrades, onychophorans and arthropods) |label2=Total group Euarthropoda |2={{clade |1={{extinct}}''Megadictyon'' 80 px |2={{clade |1={{clade |1={{extinct}}''Kerygmachela'' 80 px |2={{clade |1={{extinct}}''Pambdelurion'' 80 px |2={{clade |1={{extinct}}Opabiniidae 70 px |2={{clade |1={{extinct}} Radiodonta (e.g ''Anomalocaris'') 70 px |label2=Deuteropoda |2={{clade |1={{extinct}}''Erratus'' 70 px |2={{clade |1={{extinct}}''Sunella'' 70px |2={{clade |1={{extinct}}Isoxyidae 70px + "Great appendage bivalved forms" 70px |2={{clade |1={{clade |1={{extinct}}''Fengzhengia'' 80 px |2={{extinct}}''Kylinxia'' 70px }} |2={{clade |1={{extinct}}Megacheira 80px |2=Pan-Chelicerata 70px 70px }} |3={{clade |1={{extinct}}''Kiisortoqia'' 70px |2={{extinct}}''Bushizheia'' 70px |label3=Antennulata |3={{clade |1={{extinct}}Artiopoda (including Trilobita) 70px |label2=Mandibulata |2={{clade |1={{extinct}}Fuxianhuiida 70px |2={{clade |1={{extinct}}Hymenocarina 70px |2={{clade |1=Myriapoda 70px |2=Pancrustacea 70px 70px }}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}|label1=Panarthropoda|style=font-size:90%}}

Cladogram of Mandibulata after Laville et al. (2025):<ref>{{Cite journal |last=Laville |first=Thomas |last2=Forel |first2=Marie-Béatrice |last3=King |first3=Andrew |last4=Charbonnier |first4=Sylvain |date=2025-11-01 |title=Synchrotron X-ray tomography sheds light on the phylogenetic affinities of the enigmatic thylacocephalans within Pancrustacea |url=https://royalsocietypublishing.org/doi/10.1098/rspb.2025.1612 |journal=Proceedings of the Royal Society B: Biological Sciences |volume=292}}</ref>

{{clade|{{clade |1=†''Aquilonifer'' 60px |2={{clade |1=†''Tanazios'' |2={{clade |1={{clade |1=†''Acheronauta'' 50px |2=†''Captopodus'' }} |2={{clade |1={{clade |1=†''Nereocaris'' 50px |2={{clade |1=†Fuxianhuiida 50px |2=†Hymenocarina 50px }}}} |2={{clade |1={{clade |1=†Euthycarcinida 50px |2=Myriapoda (including centipedes and millipedes) 50px }} |label2=Pancrustacea |2={{clade |label1=Allotriocarida |1={{clade |1=Branchiopoda (tadpole shrimp/''Triops'', fairy shrimp, clam shrimp, water fleas) 50px |2={{clade |1=Hexapoda (including springtails and insects) 50px |label2=Xenocarida |2={{clade |1=Cephalocarida (horseshoe shrimp) 50px |2=Remipedia 30px }}}}}} |2={{clade |label1=Oligostraca |1={{clade |1=Branchiura (fish lice) 50px |2={{clade |1=Ostracoda 50px |2=Mystacocaridida 30px }}}} |label2=Multicrustacea |2={{clade |1=Copepoda 50px |2={{clade |1=Cirripedia (barnacles) 50px |2={{clade |1=†Cyclida (Americlidae) 50px |2={{clade |1=†Thylacocephala 50px |2={{clade |1=Malacostraca (shrimp, prawn, lobsters, mantis shrimp, crab, woodlice, etc) 50px }}}}}}}}}}}}}}}}}}}}}}}}|label1=Mandibulata}}

==References== {{Reflist|refs= <ref name=Regier>{{cite journal |author1=Jerome C. Regier |author2=Jeffrey W. Shultz |author3=Andreas Zwick |author4=April Hussey |author5=Bernard Ball |author6=Regina Wetzer |author7=Joel W. Martin |author8=Clifford W. Cunningham |year=2010 |title=Arthropod relationships revealed by phylogenomic analysis of nuclear protein-coding sequences |journal=Nature |volume=463 |pages=1079–1083 |doi=10.1038/nature08742 |pmid=20147900 |issue=7284|bibcode = 2010Natur.463.1079R |s2cid=4427443 }}</ref>

<ref name=vonJennWillDell11>{{cite journal |author1=Björn M. von Reumont |author2=Ronald A. Jenner |author3=Matthew A. Wills |author4=Emiliano Dell'Ampio |author5=Günther Pass |author6=Ingo Ebersberger |author7=Benjamin Meyer |author8=Stefan Koenemann |author9=Thomas M. Iliffe |author10=Alexandros Stamatakis |author11=Oliver Niehuis |author12=Karen Meusemann |author13=Bernhard Misof |year=2011 |title=Pancrustacean phylogeny in the light of new phylogenomic data: support for Remipedia as the possible sister group of Hexapoda |journal=Molecular Biology and Evolution |volume=29 |issue=3 |pages=1031–1045 |doi=10.1093/molbev/msr270 |pmid=22049065|doi-access=free }}</ref>

<ref name=RotaStabelli11>{{cite journal |author1=Omar Rota-Stabelli |author2=Lahcen Campbell |author3=Henner Brinkmann |author4=Gregory D. Edgecombe |author5=Stuart J. Longhorn |author6=Kevin J. Peterson |author7=Davide Pisani |author8=Herve Philippe |author9=Maximilian J. Telford |year=2011 |title=A congruent solution to arthropod phylogeny: phylogenomics, microRNAs and morphology support monophyletic Mandibulata |journal=Proceedings of the Royal Society B |volume=278 |issue=1703 |pages=298–306 |doi=10.1098/rspb.2010.0590 |pmid=20702459 |pmc=3013382}}</ref> }}

Category:Arthropod taxonomy