Chelicerata

Arachnomorpha
 * †Fuxianhuia
 * †Antennulata
 * †Emeraldella
 * †Trilobitomorpha
 * †Sidneyia
 * †Megacheira
 * †Yohoia
 * †Alalcomenaeus
 * †Leanchoilia
 * Chelicerata
 * Pycnogonida
 * †Palaeoisopus
 * Pycnogonum
 * †Haliestes
 * Euchelicerata
 * †Offacolus
 * Prosomapoda
 * †Weinbergina
 * †Venustulus
 * †Camanchia
 * †Legrandella
 * Xiphosura
 * †Kasibelinurus
 * †Willwerathia
 * Xiphosurida
 * †Lunataspis
 * †Bellinurina
 * Limulina
 * Planaterga
 * †Pseudoniscus
 * †Cyamocephalus
 * †Pasternakevia
 * †Bunodes
 * †Limuloides
 * †Bembicosoma
 * Dekatriata
 * †Chasmataspidida
 * Sclerophorata
 * Arachnida
 * †Eurypterida
 * †Eurypterida