Antiarcha

plural noun

An·​ti·​ar·​cha

: a subclass or other division of Placodermi comprising small Devonian freshwater ostracoderms having complex bony armor on the anterior part of the body and a pair of pectoral appendages resembling paddles

Word History

Etymology

New Latin, from anti- entry 1 + -archa (from Greek archos anus); from the contrast in the location of the anus with that of the Urochordata

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