Anaspida

Group of extinct jawless vertebrates

Anaspida ("shieldless ones") is an extinct group of jawless fish that existed from the early Silurian period to the late Devonian period. They were classically regarded as the ancestors of lampreys, but this is denied in recent phylogenetic analyses, although some analyses show these groups would be at least related. Anaspids were small marine fish that lacked a heavy bony shield and paired fins, but were distinctively hypocercal.

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