Acanthodians are a type of ancient fish dating back the late Silurian period, often being called spiny sharks.

Anyway, Pete found a decomposing spiny shark washed up on the bank, and now he's all excited.

Other common names for this species are spinous shark and spiny shark.

Climatius (meaning inclined fish or tilted fish) is an extinct genus of spiny shark.

Like most other "spiny sharks", the Climatiiformes had sharp spines.

Despite being called "spiny sharks," acanthodians predate sharks.

The largest spiny sharks Ischnacanthus .

Acanthodii (sometimes called spiny sharks) is a class of extinct fishes, sharing features with both bony fish and cartilaginous fish.

The popular name "spiny sharks" is really a misnomer for these early jawed fishes.

Ischanacanthiformes is an order of Acanthodii or spiny sharks.