Penthorum

{{Short description|Genus of flowering plants}}

{{Automatic taxobox

|image = Penthorum_chinense2.jpg

|image_caption = Penthorum chinense

|parent_authority = Rydb. ex Britt.{{Cite journal |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 |url=http://onlinelibrary.wiley.com/doi/10.1046/j.1095-8339.2003.t01-1-00158.x/pdf | format= PDF |accessdate=2013-07-06 |doi=10.1111/j.1095-8339.2009.00996.x |doi-access=free |hdl=10654/18083 |hdl-access=free }}

|taxon = Penthorum

|authority = L.

|subdivision_ranks = Species

|subdivision = Penthorum chinense

Penthorum sedoides{{cite web | title = Penthorum sedoides L. | work = Flora of Missouri | url = http://www.efloras.org/florataxon.aspx?flora_id=11&taxon_id=220010118 }}

| range_map = Penthoraceae Distribution.svg

| range_map_caption = The range of Penthorum.

|type_species=P. sedoides L.

}}

Penthorum is a genus of plants in the order Saxifragales. They are erect herbaceous perennials about half a meter tall. The genus consists of two species, one from east Asia and one from eastern North America.{{cite web | url = http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=124450 | work = Flora of China | title = Penthorum Linnaeus }} It is variously classified in the family Saxifragaceae or its own family Penthoraceae.{{cite web | url = http://www.ars-grin.gov/cgi-bin/npgs/html/family.pl?843 | title = Penthoraceae Rydb. ex Britton, nom. cons. | work = Germplasm Resources Information Network | access-date = 2009-02-15 | archive-url = https://web.archive.org/web/20090506190418/http://www.ars-grin.gov/cgi-bin/npgs/html/family.pl?843 | archive-date = 2009-05-06 | url-status = dead }} Its closest relatives may be in Haloragaceae.