placodermi(n = noun.animal) class placodermi - extinct group of bony-plated fishes with primitive jaws;
is a kind of class
is a member of craniata, subphylum craniata, subphylum vertebrata, vertebrata
An extinct group of fishes, supposed to be ganoids. The body and head were covered with large bony plates. See Illust. under Pterichthys, and Coccosteus. [1913 Webster]