Agnatha

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Related to agnathans: Chondrichthyes, Ostracoderms, Placoderms, Chondrichthyans, Gnathostomes, Acanthodians

Agnatha

aquatic, jawless, fish-like vertebrates characterized by fewer than two pairs of limbs (fins). The group is often given the status of a subphylum to separate it from other vertebrates with jaws which are included in the subphylum Gnathostomata. The Agnatha includes lampreys, hagfish, and the fossil OSTRACODERMI.