Mandibulata

Mandibulata Temporal range: Cambrian Stage 3–Recent PreꞒ Ꞓ O S D C P T J K Pg N
The mandibles of a bull ant
Life restoration of Odaraia , an early mandibulate belonging to Hymenocarina with mandibles present near the mouth
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Clade:	Mandibulata de Clairville, 1798
Subdivisions
† Acheronauta ? † Aquilonifer †Bradoriida? †Cambropachycopidae? † Cambropodus ? † Captopodus ? † Cascolus ? †Euthycarcinoidea †Fuxianhuiida? †Hymenocarina † Martinssonia ? † Musacaris ? Myriapoda †Oelandocarididae? Pancrustacea †Phosphatocopina? † Rhyniognatha ? †Skaracarida? † Tanazios ? †Thylacocephala?

The clade Mandibulata constitutes one of the major subdivisions of the phylum Arthropoda, alongside Chelicerata. Mandibulates include the crustaceans, myriapods (centipedes and millipedes, among others), and 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.

The mandibulates are divided between the extant groups Myriapoda (millipedes & 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. ^{[1] [2] [3]}

A number of extinct groups have also been placed in Mandibulata, including Hymenocarina ^[4] , Euthycarcinoidea, ^[5] and possibly Fuxianhuiida. ^[6]

Arthropoda	Mandibulata Pancrustacea (crustaceans and hexapods) Myriapoda (centipedes, millipedes, and allies) Chelicerata (sea spiders, horseshoe crabs, and arachnids)

Taxonomic history

The name "Mandibulata" was originally used for a subgroup of insects by Joseph Philippe de Clairville in 1798. ^[7] 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 simlarities, including but not limited to the presence of mandibles. ^[8] This proposal was contested by some other 20th century scholars, who considered mandibles the result of convergent evolution, ^[9] though the existence of Mandibulata is now widely accepted based on genetic evidence. ^[10]

See also

• Atelocerata
• Marrellomorpha
• Myriochelata
• Pancrustacea
• Crustaceomorpha
• Antennulata
• Arachnomorpha
• Uniramia

References

4. Izquierdo-López, Alejandro; Caron, Jean-Bernard (August 2024). "The Cambrian Odaraia alata and the colonization of nektonic suspension-feeding niches by early mandibulates". Proceedings of the Royal Society B: Biological Sciences. 291 (2027). doi:10.1098/rspb.2024.0622. ISSN   1471-2954. PMC   11463219 . PMID   39043240.
5. Edgecombe, Gregory D.; Strullu-Derrien, Christine; Góral, Tomasz; Hetherington, Alexander J.; Thompson, Christine; Koch, Marcus (2020). "Aquatic stem group myriapods close a gap between molecular divergence dates and terrestrial fossil record". Proceedings of the National Academy of Sciences. 117 (16): 8966–8972. doi: 10.1073/pnas.1920733117 . PMC   7183169 . PMID   32253305. S2CID   215408474.
6. Aria, Cédric; Zhao, Fangchen; Zhu, Maoyan (September 2021). "Fuxianhuiids are mandibulates and share affinities with total-group Myriapoda". Journal of the Geological Society. 178 (5). doi:10.1144/jgs2020-246. ISSN   0016-7649.
7. Schellenberg, Johann Rudolf; Joseph Philippe de, Clairville (1798). Helvetische Entomologie, oder, Verzeichniss der schweizerischen Insekten nach einer neuen Methode geordnet : mit Beschreibungen und Abbildungen. Zürich: Bei Orell, Füssli und Compagnie.
8. SNODGRASS, R. E. 1938. Evolution of the Annelida, Onychophora, and Arthropoda. Smithsonian Miscellaneous Collections97: 1–159.
9. Edgecombe, G.D. ∙ Richter, S. ∙ Wilson, G.D.F. The mandibular gnathal edges: Homologous structures throughout Mandibulata? Afr. Invertebr. 2003; 44:115-135
10. Giribet, Gonzalo; Edgecombe, Gregory D. (June 17, 2019). "The Phylogeny and Evolutionary History of Arthropods". Current Biology. 29 (12): R592 –R602. doi:10.1016/j.cub.2019.04.057. ISSN   0960-9822.