Creatures that lived in the Ordovician period; a geologic period and system that extends from the end of the Cambrian Period, about 485.4 ± 1.9 million years ago, to the beginning of the Silurian Period, about 443.8 ± 1.5 Ma.

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Pages in category "Ordovician Creatures"

The following 2 pages are in this category, out of 2 total.