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Ordovician
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Ordovician
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note:
the locations of the continents and ecosystems are correct for the EARLY
Ordovician, but the fossils shown are for the entire Ordovician period.
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Heterocrinus |
Protopaleaster |
Streptelasma |
Modiolopis |
Pseudogygites |
Cupulocrinus |
Calymene |
Asaphus |
Astraspis
desiderata |
Sacabambaspis |
Flexicalymene |
Dikecephalina |
Tetragraphus
— not a fish! a hemichordate! |
Arandaspis |
Clidochirus |
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490
million years ago |
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Maclurites |
Camoceras |
