Haplostigma
Encyclopedia
Haplostigma is a genus of arborescent lycopod, found only in the early part of the Middle Devonian
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Devonian
The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...
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