Oxypolis rigidior

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Asterids
Cladus: Campanulids
Ordo: Apiales

Familia: Apiaceae
Subfamilia: Apioideae
Tribus: Oenantheae
Genus: Oxypolis
Species: Oxypolis rigidior
Name

Oxypolis rigidior (L.) Raf., 1830
Synonyms

Archemora ambigua (Nutt.) DC.
Archemora denticulata (Baldw.) DC.
Archemora rigidia (L.) DC.
Archemora rigidior var. ambigua (Nutt.) A. Gray
Archemora serrata Raf.
Archemora tricuspidata (Ell.) DC.
Archemora trifoliata Raf.
Oenanthe ambigua Nutt.
Oenanthe rigidia (L.) Crantz
Oxypolis denticulata (Baldw.) Raf.
Oxypolis denticulata (Baldwin) J.R.Edm.
Oxypolis longifolia (Pursh) Small
Oxypolis rigidior var. ambigua (Nutt.) B.L. Rob.
Oxypolis rigidior var. longifolia (Pursh) Britton
Oxypolis rigidus Britton
Oxypolis tricuspidata (Ell.) Rafin.
Oxypolis turgida Small
Pastinaca ambigua (Nutt.) Torr.
Pastinaca denticulata (Baldw.) D. Dietr.
Pastinaca tricuspidata (Ell.) D. Dietr.
Peucedanum rigidius (L.) Baill.
Peucedanum rigidius var. ambiguum (Nutt.) Wood
Sium denticulatum Baldw. ex Ell.
Sium longifolium Pursh
Sium rigidius L.
Sium tricuspidatum Ell.
Tiedemannia rigida (L.) Coult. & J. N. Rose
Tiedemannia rigidior var. ambigua (Nutt.) J. M. Coult. & Rose

Distribution
Native distribution areas:

Continental: Northern America
USA (Alabama, Arkansas, District of Columbia, Delaware, Florida, Georgia, Iowa, Illinois, Indiana, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Missouri, Mississippi, North Carolina, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, Wisconsin, West Virginia), Canada (Ontario)

References: Brummitt, R.K. 2001. TDWG – World Geographical Scheme for Recording Plant Distributions, 2nd Edition
References

Rafinesque-Schmaltz, C.S., Bull. Bot., Geneva 218. 1830 "rigida"

Links

Hassler, M. 2018. Oxypolis rigidior. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2018. Species 2000 & ITIS Catalogue of Life. Published on the internet. Accessed: 2018 Aug. 25. Reference page.
International Plant Names Index. 2018. Oxypolis rigidior. Published online. Accessed: Aug. 25 2018.
The Plant List 2013. Oxypolis rigidior in The Plant List Version 1.1. Published on the internet. Accessed: 2018 Aug. 25.
Tropicos.org 2018. Oxypolis rigidior. Missouri Botanical Garden. Published on the internet. Accessed: 2018 Aug. 25.
USDA, ARS, Germplasm Resources Information Network. Oxypolis rigidior in the Germplasm Resources Information Network (GRIN), U.S. Department of Agriculture Agricultural Research Service. Accessed: 07-Oct-06.

Vernacular names
English: Stiff cowbane

Oxypolis rigidior, known as cowbane, common water dropwort,[1] stiff cowbane,[2] or pig-potato, is a species of flowering plant in the carrot family native to eastern North America. It is a perennial wildflower found in wet habitats.[3][4][5] Oxypolis rigidior is poisonous to mammals.

Description

Oxypolis rigidior is 2–6 foot tall perennial herb of eastern North America. Its leaves are compound, odd-pinnate with 7-11 leaflets, and have variable shape. Umbels of 3 mm white flowers appear August to October. Flat fruits with conspicuous "wings" appear October through November.[5][3]

The variable leaf shape may make identification challenging. Water hemlock, a related very poisonous species, which sometimes even shares the common name "cowbane", is similar, as is the closely related Savanna cowbane (Oxypolis ternata).[5][3]
Taxonomy

Two varieties have been described, O. rigidior var. rigidior and O. rigidior var. ambigua.[5]
Toxicity

Both roots and top parts are poisonous to mammals.[6][7]
References

"Oxypolis rigidior". www.minnesotawildflowers.info. Minnesota Wildflowers. Retrieved 21 August 2020.
"Lady Bird Johnson Wildflower Center - The University of Texas at Austin". www.wildflower.org.
Peterson, Roger Tory; McKenny, Margaret (1968). A Field Guide to Wildflowers Northeastern and Northcentral North America. New York, NY, USA: Houghton Mifflin. p. 52.
"Oxypolis rigidior (L.) Raf". USDA. Retrieved July 21, 2015.
Weakley, Alan S. (May 2015). Flora of the Southern and Mid-Atlantic States (PDF). Chapel Hill, NC, USA: The University of North Carolina Herbarium. p. 1236. Retrieved 8 July 2015.
Dr. John Hilty. "Cowbane (Oxypolis rigidior)". illinoiswildflowers.info/. Retrieved July 21, 2015.
Cowbane at the Encyclopædia Britannica