Vertebrate Fossils

{ Fossil vertebrates (Phylum Chordata) are relatively rare fossils, although diligent searching can turn up highly prized specimens. Many fossil vertebrate remains are so rare, and scientifically important, that it is recommended that collectors contact the nearest university geology department, museum, or the Ohio Historical Society. Ohio has an important record of fossil vertebrates that in some cases has characterized life in that particular point in geologic history.

FOSSIL FISHES

Agnathans

The earliest known fish-like animals appeared in the Cambrian Period. By the Ordovician Period, a diverse fauna of jawless, bottom-feeding, armored fishes were present in nearshore marine environments. These fishes belonged to a group known as Agnatha (jawless). Although remains of agnathans have been found in many areas of the world in Ordovician rocks, none have been in Ohio rocks representing this time period. Perhaps Ohio was too far offshore for these fishes at that time. Agnathan remains are unknown from Ohio Silurian rocks as well.

However, remains of Agnathan fishes are known from a unique deposit of Early Devonian age that was discovered in a quarry in northwestern Ohio in the 1920 [[Category:{$topic}]]