Athyrium angustum

Athyrium angustum is known as the northern lady fern, native to northeastern North America. It was long included in the superspecies "Athyrium filix-femina", but is now largely recognized as a distinct species.
"Athyrium angustum" has a more southern counterpart, "Athyrium asplenioides". This species, the southern lady fern, has a broader frond, especially at the base.
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