Biology:Mandibulata

The clade Mandibulata constitutes one of the major subdivisions of the phylum Arthropoda, 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.

Phylogeny

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.

Some extinct groups have been placed in Mandibulata, including Hymenocarina, Euthycarcinoidea, and Fuxianhuiida.

Cladogram after O'Flynn et al, 2023:

Total group

† "Gilled lobopodians" (Pambdelurion, Kerygmachela)60px       †Opabinia 60px       † Radiodonta (e.g Anomalocaris) 60px   Deuteropoda     † Kylinxia 60px     † Fengzhengia 60px           † Kiisortoqia 60px     † Bushizheia 60px     Total group   † Megacheira 60px       † Habeliida 60px       † Mollisonia 60px     Chelicerata (horseshoe crabs, sea spiders, arachnids, etc) 60px       Chelicerata       † "Great appendage bivalved forms" (Occacaris, Forfexicaris)     † Isoxyida 60px         † Artiopoda (inc. Trilobita) 60px   Mandibulata   † Fuxianhuiida 60px       Myriapoda (millipedes, centipedes, etc) 60px       † Hymenocarina 60px     Pancrustacea (crustaceans, insects, etc) 60px

Arthropoda

 

Cladogram of Mandibulata after Laville et al. (2025):

Mandibulata

†Aquilonifer 50px       †Tanazios         †Acheronauta 50px     †Captopodus           †Nereocaris 50px       †Fuxianhuiida 50px     †Hymenocarina 50px             †Euthycarcinida 50px       †Arthropleura 50px     Myriapoda crown group (including centipedes and millipedes) 50px       Pancrustacea Allotriocarida   Branchiopoda (tadpole shrimp/Triops, fairy shrimp, clam shrimp, water fleas) 50px       Hexapoda (including springtails and insects) 50px   Xenocarida   Cephalocarida (horseshoe shrimp) 50px     Remipedia 30px               Branchiura (fish lice) 50px       Ostracoda 50px     Mystacocaridida 30px       Multicrustacea   Copepoda 50px       Cirripedia (barnacles) 50px       †Cyclida (Americlidae) 50px       †Thylacocephala 50px       Malacostraca (shrimp, prawn, lobsters, mantis shrimp, crab, woodlice, etc) 50px

Taxonomic history

The name "Mandibulata" was originally used for a subgroup of insects by Joseph Philippe de Clairville in 1798. 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. This proposal was contested by some other 20th century scholars, who considered mandibles the result of convergent evolution, though the existence of Mandibulata is now widely accepted based on genetic evidence.

Characteristics

Mandibulates are characterized by a head tagma that has Antennae and three feeding appendages that make up the mandible. There is a relatively low level of diversity in the clade.

See also

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

References

Wikidata ☰ Q1633496 entry