Mandibulata

Taxonomy

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 monophyly of Mandibulata is now widely accepted based on genetic evidence.

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. This grouping may also contain other extinct arthropod groups like Marrellomorpha.

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 Liu et al, 2026:

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