Pteraspis
/təˈraspɪs/Palaeontology
noun
A genus of armoured jawless fossil fishes (ostracoderms) of the Lower Devonian with the anterior end enclosed by a shield of bony plates; a fish of this genus.
Origin
Mid 19th century. From scientific Latin Pteraspis from ancient Greek πτερόν + ἀσπιδ-, ἀσπίς shield.