Editing Polygonaceae (section)

==Taxonomy==
Polygonaceae are very well-defined and have long been universally recognized. In the [[APG III system]], the family is placed in the [[Order (biology)|order]] [[Caryophyllales]].<ref name="apgiii">{{Citation |last=Angiosperm Phylogeny Group |year=2009 |title=An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III |journal=Botanical Journal of the Linnean Society |volume=161 |issue=2 |pages=105–121 |doi=10.1111/j.1095-8339.2009.00996.x |doi-access=free|hdl=10654/18083 |hdl-access=free }}</ref> Within the order, it lies outside of the large [[clade]] known as the core Caryophyllales.<ref name="Brockington2009">{{cite journal |last1=Brockington |first1=Samuel F. |last2=Alexandre |first2=Roolse |last3=Ramdial |first3=Jeremy |last4=Moore |first4=Michael J. |last5=Crawley |first5=Sunny |last6=Dhingra |first6=Amit |last7=Hilu |first7=Khidir |last8=Soltis |first8=Douglas E. |last9=Soltis |first9=Pamela S. |year=2009 |title=Phylogeny of the Caryophyllales sensu lato: Revisiting hypotheses on pollination biology and perianth differentiation in the core Caryophyllales |url=http://hdl.handle.net/10919/49132 |journal=International Journal of Plant Sciences |volume=170 |issue=5 |pages=627–643 |doi=10.1086/597785 |hdl=10919/49132 |s2cid=58921387 |hdl-access=free |access-date=2020-09-15 |archive-date=2023-01-20 |archive-url=https://web.archive.org/web/20230120084848/https://vtechworks.lib.vt.edu/handle/10919/49132 |url-status=live }}</ref> It is a [[sister taxon|sister]] to the family [[Plumbaginaceae]], which it does not resemble [[Plant morphology|morphologically]].<ref name="apweb">Peter F. Stevens. 2001 onwards. Angiosperm Phylogeny Website At: Missouri Botanical Garden Website. (see ''External links'' below).</ref>
[[File:Polygonum plebeium W IMG 0462.jpg|thumb|250px|''[[Polygonum plebeium]]'' or small knotweed]]

The last comprehensive revision of the family was published in 1993 by John Brandbyge as part of [[Kubitzki system|''The Families and Genera of Vascular Plants'']].<ref name="brandbyge1993"/> Brandbyge followed [[List of systems of plant taxonomy|earlier systems]] of [[History of plant systematics|plant classification]] in dividing Polygonaceae into two [[subfamilies]], [[Eriogonoideae]] and [[Polygonoideae]]. Since 1993, the [[Circumscription (taxonomy)|circumscriptions]] of these two subfamilies have been changed in light of [[phylogenetic]] [[Research|studies]] of [[DNA sequence]]s.<ref name="sanchez2009">{{cite journal |last1=Sanchez |first1=Adriana |last2=Schuster |first2=Tanja M. |last3=Kron |first3=Kathleen A. |year=2009 |title=A large-scale phylogeny of Polygonaceae based on molecular data |journal=International Journal of Plant Sciences |volume=170 |issue=8 |pages=1044–1055 |doi=10.1086/605121 |s2cid=84694521}}</ref> Genera related to ''Coccoloba'' and ''Triplaris'' were moved from Polygonoideae to Eriogonoideae. The genus ''Symmeria'' does not belong to either of these subfamilies because it is a sister to the rest of the family.<ref name="burke2010">{{cite journal |last1=Burke |first1=Janelle M. |last2=Sanchez |first2=Adriana |last3=Kron |first3=Kathleen |last4=Luckow |first4=Melissa |year=2010 |title=Placing the woody tropical genera of Polygonaceae: A hypothesis of character evolution and phylogeny |journal=American Journal of Botany |volume=97 |issue=8 |pages=1377–1390 |doi=10.3732/ajb.1000022 |pmid=21616890}}</ref> ''Afrobrunnichia'' might constitute a new subfamily as well.<ref name="sanchez&kron2009">{{cite journal |last1=Sanchez |first1=Adriana |last2=Kron |first2=Kathleen A. |year=2009 |title=Phylogenetic relationships of ''Afrobrunnichia'' Hutch. & Dalziel (Polygonaceae) based on three chloroplast genes and ITS |journal=Taxon |volume=58 |issue=3 |pages=781–792 |doi=10.1002/tax.583008}}</ref>

Brandbyge wrote descriptions for 43 genera of Polygonaceae in 1993.<ref name="brandbyge1993"/> Since then, a few more genera have been erected, and some [[Segregate (taxonomy)|segregates]] of ''Brunnichia'', ''Eriogonum'', and ''Persicaria'' have been given generic [[Taxonomic rank|status]] in major works.<ref name="freeman2005"/><ref name="burke2010"/><ref name="li2003">Anjen Li, Bojian Bao, Alisa E. Grabovskaya-Borodina, Suk-pyo Hong, John McNeill, Sergei L. Mosyakin, Hideaki Ohba, and Chong-wook Park. 2003. "Polygonaceae" pages 277-350. In: Zhengyi Wu, Peter H. Raven, and Deyuan Hong (editors). ''Flora of China'' volume 5. Science Press: Beijing, China; Missouri Botanical Garden Press: St. Louis, Missouri, USA.</ref> Some of the genera were found not to be [[monophyletic]] and their limits have been revised. These include ''Ruprechtia'', ''Eriogonum'', ''Chorizanthe'', ''Persicaria'', ''Aconogonon'', ''Polygonum'', ''Fallopia'', and ''Muehlenbeckia''.