acanthodian
n. C2 Proficiency acan·tho·di·an
n. a type of ancient fish that lived in the oceans millions of years ago. These fish had a unique body shape and were some of the first animals to have jaws.
n. a member of an extinct group of jawed fish that lived during the Silurian and Devonian periods. Characterised by a distinctive body shape and the presence of a single pair of gill slits.
The acanthodian is an early example of a jawed fish.
Fossils of the acanthodian have been found in marine sediments, providing insight into the evolution of early vertebrates.
The acanthodian represents a critical transitional stage in the development of modern fish, bridging the gap between jawless and fully developed jawed vertebrates.