Lifestyles restoration of Cephalaspis, a conventional osteostracan, swimming over the substrate. Image credit: Hugo Salais, Metazoa Studio.
Osteostraci (osteostracans) is a team of extinct bony-armored jawless fish that lived in what are genuinely North The US, Europe and Asia from the Center Silurian to Unhurried Devonian epoch.
These backside-space creatures had been doubtlessly rather appropriate swimmers, possessing dorsal fins, paired pectoral fins, and a stable tail.
The defend of bone covering their head formed a single section, and so presumably failed to develop throughout grownup existence. Many possessed extraordinary horn-appreciate extensions from the front of their heads.