Stigmaria

Stigmaria, a fossil lycopsid rhizome.

In situ lycopsid with attached stigmarian roots. Joggins Formation (Pennsylvanian), Cumberland Basin, Nova Scotia.

Bedding plane view of a flattened Stigmaria preserved atop a shallow-water carbonaceous limestone in the Joggins Formation (Pennsylvanian), Cumberland Basin, Nova Scotia.

Stigmaria are a type of branching tree root fossil found in Carboniferous rocks. They were the roots of coal forest lycopsid trees such as Sigillaria and Lepidodendron. Each trunk tended to have four of those roots. Stigmaria is a form taxon, as the genus and species of the plant bearing the root is not identified.

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