Placodermi

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Placodermi

[‚pla·kə′dər·mē]
(paleontology)
A large and varied class of Paleozoic fishes characterized by a complex bony armor covering the head and the front portion of the trunk.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Placodermi

 

a class of extinct fishes that lived during the Devonian. Their length was up to 5–6 m. The head and anterior part of the trunk were covered with an armor of bony plates of cutaneous origin. The plates were nodular and ridged. The head and trunk sections of the armor were articulated, and the jaws consisted of pointed bony plates. There were two subclasses: Arthrodira and Antiarchi (which included the genus Bothriole-pis).

REFERENCE

Drushits, V. V., and O. P. Obrucheva. Paleontologiia, 2nd ed. [Moscow] 1971.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.