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Related to Placoderms: Chondrichthyes, labyrinthodonts, Acanthodians


Any of various extinct jawed fishes of the group Placodermi of the Silurian and Devonian Periods, having bony plates of armor covering the head and thorax. Placoderms were among the first jawed vertebrates.

[New Latin Placodermī, class name : Greek plax, plak-, flat stone, plate; see plāk- in Indo-European roots + -derm.]


(Palaeontology) any extinct bony-plated fishlike vertebrate of the class Placodermi, of Silurian to Permian times: thought to have been the earliest vertebrates with jaws
[C19: from Greek plac-, plax a flat plate + -derm]


(ˈplæk əˌdɜrm)

any of various extinct jawed fishes of the class Placodermi, chiefly of the Devonian Period: many were armored in bony plates.
[1855–60; < New Latin Placodermi name of the class, pl. of placodermus=placo- (< Greek; see placoid, -o-) + -dermus -derm]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.placoderm - fish-like vertebrate with bony plates on head and upper body; dominant in seas and rivers during the Devonian; considered the earliest vertebrate with jaws
aquatic vertebrate - animal living wholly or chiefly in or on water
class Placodermi, Placodermi - extinct group of bony-plated fishes with primitive jaws
References in periodicals archive ?
Scientists were excited by its mix of traits from placoderms - an extinct armoured fish - and bony fish, which gave rise to all modern fish that have jaws and skeletons made of bone.
They are represented by undetermined placoderms, acanthodians and sarcopterygians (Fig.
Called placoderms, these extinct animals were among the earliest vertebrates with jaws.
Among other things it contains placoderms, an extinct group that includes some of the earliest jawed fish.
These previously discovered eurypterids are from the western exposure of the Campbellton Formation and are believed to have inhabited a coastal deltaic setting, along with a rich vertebrate assemblage that included cephalaspids, placoderms, acanthodians, and sharks.
Several marine fossils not found in underlying formations suddenly appear here, including those of gastropods; crinoids; rare corals; small conodonts (eel-like creatures); and armored, plate-mouthed fish known as placoderms.
The volume also highlights the Devonian period with three articles on placoderms, the Gogo fish fossils, and the origin of whales.
Dunkleosteus was one of many species of placoderms, a diverse group of armoured fishes that dominated aquatic ecosystems during the Devonian period, from 415 million to 360 million years ago.
The sculpture of stellate tubercles and open lateral line canals of Lophosteus platelets have superficial similarities with some placoderms, for example, with radotinids.
Scientists were excited by its mUG SHOT: mix of traits from placoderms - an extinct armoured fish - and bony fish, which gave rise to all modern fish that have jaws and skeletons made of bone.
We could then make comparisons with the embryology of living vertebrates, thus demonstrating that placoderms possessed teeth," he explained.