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When did the earliest sphenophytes appear in Earth’s history?
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Equisetopsida
Giant horsetail of Europe (Equisetum telmateia).
The earliest sphenophytes appeared during the Devonian Period, which spanned approximately 419 to 359 million years ago. While the class Equisetopsida reached significant diversity and prominence later during the Carboniferous Period, fossil evidence confirms their origins date back to the Devonian.12