The Tetraconata is a clade consisting of the Crustacea (crabs, lobsters, and shrimp) and Hexapoda (insects). It is the sister clade to the Myriochelata. Together the two constitute the phylum Arthropoda

The evidence for this clade derives from molecular data and morphological characteristics. The molecular data consists of comparisons of nuclear ribosomal RNA genes, mitocondrial ribosomal RNA genes, and protein coding genes. The morphological data consists of ommatidial structures (see arthropod eye), the presence of neuroblasts, and the form and style of axonogenesis by pioneer neurons.^[1][2]

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