Platyethmoidia antarctica was named by Young et al. (1992) [A cosmine-covered osteolepiform with a short broad fronto-ethmoidal shield (breadth/length index 125), a pronounced preorbital and slight postorbital corner, and external nares partly visible from above. Lower jaw 4.5 times as long as deep. Clavicle with a broad ascending process and anterior margin. ]. Its type specimen is AMF 54405, a partial skull (an incomplete fronto-ethmoidal shield), and it is a 3D body fossil. Its type locality is Young et al 1992 Devonian Fish Locality 8, which is in a Givetian marine siltstone in the Aztec Siltstone Formation of Antarctica.