Uniramia

The Uniramia are a group of arthropods, comprising the Hexapoda (insects and allies) and Myriapoda (centipedes, millipedes, and related forms). They are united by the nature of the appendages on the head and the walking legs. The Crustacea are generally considered the closest relatives of the Uniramia, and sometimes they are united as the Mandibulata. However, new studies suggest that the Myriapoda are not be closer related to the Hexapoda than the Crustacea, in which case the Uniramia would be abandoned. In proposals treating the arthropods as a polyphyletic group, the Onychophora were included here, but this has little support.