Crossopterygii

Tribe of Ganoids broad jugular plates instead of branchiostegal rays; and with pointed diphy cercal tail; the fins as well as body are covered with scales, which may be either thin and cycloid, or strong and rhomboid. The "Mud-fish" of Africa ( Polypterus ), with rhomboid scales, and a dorsal fin divided into many small ones, illustrates the group. This fish unites the Ganoids with the Dipnoi and Amphibia .