Cancroidea is a superfamily of crabs, comprising the families Atelecyclidae and Cancridae. http://boletinsgm.igeolcu.unam.mx/bsgm/vols/epoca04/6502/%2810%29Osso.pdf Four other families have been separated into new superfamilies: Cheiragonidae into Cheiragonoidea, Corystidae into Corystoidea, and both Pirimelidae and Thiidae into Portunoidea. Montezumellidae has been moved from Cancroidea to its own superfamily Montezumelloidea.
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