Are Palmer’s elm-leaf goldenrod and the smooth elm-leaf goldenrod real? The Angiosperms353 kit provides within-species signal in Solidago ulmifolia s.l.

James Beck, Morgan Markley, Mackenzie Zielke, Justin Thomas, Haley Hale, Lindsay Wiliams & Matthew Johnson
Abstract — The genus Solidago represents a taxonomically challenging group due to its sheer number of species, putative hybridization, polyploidy, and shallow genetic divergence among species. Here we use a dataset obtained exclusively from herbarium specimens to evaluate the status of Solidago ulmifolia var. palmeri, a morphologically subtle taxon potentially confined to Alabama, Arkansas, Mississippi, and Missouri. A multivariate analysis of both discrete and continuous morphological data revealed no clear distinction between S. ulmifolia var....
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