Podolaspis
lerichei
Class
Heterostraci, Order Pteraspidiformes,
Family Pteraspididae
Geological
Time: Lower Devonian
Size: Fossil
fish is 90 mm long
Fossil Site:
Podolia, Ukraine
Description:
The Heterostracans were a marvelously diverse group of agnathan
fish. Typically there are two large bony plates protecting the
body, one on the dorsal and one on the ventral side. They arose
during the Silurian and achieved their greatest diversity during
the Devonian. One of the most successful groups were the pteraspids,
meaning wing shield, a term that refers to the spines that projected
from the sides of the body of many of them. Seen here is the
body shield, rostral plate, and right corneal shield (wing) far
more than what is typically what is found. It is not known whether
any remnants of the dorsal spine are present under the matrix
at the posterior border of the dorsal plate. Few posterior elements
are known; the artist’s life reconstruction is based upon
other related types. The species went extinct at the end of the
Lower Devonian, leaving no descendants.
Also
see: Paleozoic
Fish Fossils |
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