Polygonum Linnaeus. Subfamily: Polygonoideae. Tribe: Polygoneae. Common name: Knotweed.
A genus of about 45 species, herbs, of temperate regions of the Northern Hemisphere. Based on morphology, Ronse Decraene, Hong, & Smets (2004) suggested that Polygonella should be merged into Polygonum, as part of section Duravia; the close relationship of Polygonella and Polygonum section Duravia was confirmed using molecular evidence by Schuster, Reveal, & Kron (2011). We support a treatment in which Polygonum, Polygonella, and Duravia are recognized as three monophyletic genera; combinations are not yet available to treat all members of section Duravia at generic rank as genus Duravia, however.
References: Brandbyge (1993) In Kubitzki, Rohwer, & Bittrich (1993); Costea & Tardif (2003a); Costea, Tardif, & Hinds (2005f) In Flora of North America Editorial Committee (2005); Horton (1961); Ronse De Craene, Hong, & Smets (2004); Schuster, Reveal, & Kron (2011). Show full citations.
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© Scott Ward | Polygonum glaucum | Original Image ⭷
© John Gwaltney | Persicaria | Original Image ⭷
© John Gwaltney | Persicaria | Original Image ⭷
© Erik Danielson | Polygonum aviculare ssp. buxiforme source | Original Image ⭷
© Ryan Sorrells, some rights reserved (CC BY), uploaded by Ryan Sorrells | Polygonum achoreum source | Original Image ⭷Feedback
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