acanthodean
adj. C2 Proficiency acan·th·odean
adj. relating to a group of ancient fish that lived in the oceans over 400 million years ago. These fish had bony plates and spines on their backs.
adj. relating to or characteristic of the Acanthodii, an extinct group of jawed vertebrates that lived during the Paleozoic era. Often used in paleontological and evolutionary biology contexts.
The fossil shows the acanthodean fish's unique spines.
Scientists studied the acanthodean remains to understand how early jawed fish evolved into modern sharks and rays.
The discovery of acanthodean fossils in the limestone layers provided critical evidence for the transition from jawless to jawed vertebrates during the Silurian period.