Agalinis purpurea is 10 to 120 centimeters tall. The stem is slender, with spreading branches. It has simple opposite leaves, which are 10 to 40 millimeters long, and only 0.5 to 2 millimeters wide. The flowers are racemose on the branches. They are borne on 1 to 8 millimeter long pedicles. Each flower is bilaterally symmetrical, with five 20 to 38 millimeter long petals fused into a corolla tube, and four stamens. The fruit is a round 4 to 6 millimeter long dry capsule that splits open when ripe.
Distribution and habitat
Agalinis purpurea is widely distributed in the eastern United States, although local distribution may be spotty. It has been recorded in Alabama, Arkansas, Connecticut, Washington, D.C., Delaware, Florida, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Louisiana, Massachusetts, Maryland, Michigan, Minnesota, Missouri, Mississippi, North Carolina, Nebraska, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Virginia, Wisconsin, and West Virginia. It has also been recorded in the Canadian province of Ontario. In Virginia, it grows in habitats such as marshes, swamps, interdune swales, and old fields. The presence of this species is dependent on appropriate habitat, and it may be eliminated from an area by development, changes in land use, or competition with invasive species.
Like other members of the genus Agalinis, this species is hemiparasitic on a variety of hosts, particularly graminoids. Agalinis purpurea uses haustoria to connect it's roots with those of it's host plants, but it also has green tissues, and performs photosynthesis.
This species is a member of the genus Agalinis, which was formerly placed in the Scrophulariaceae family, but has more recently been placed in the Orobanchaceae family, in keeping with the findings of the Angiosperm Phylogeny Group.
- "Agalinis purpurea (L.) Pennell - The Plant List". Retrieved January 28, 2014. The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/
- "Plants Profile for Agalinis purpurea (purple false foxglove)". Retrieved January 28, 2014. USDA, NRCS. 2014. The PLANTS Database (http://plants.usda.gov). National Plant Data Team, Greensboro, NC 27401-4901 USA.
- "Agalinis purpurea (purple agalinis, purple false-foxglove): Go Botany". Retrieved January 28, 2014. Copyright © 2011-2013 New England Wild Flower Society (http://www.newenglandwild.org)
- Britton, Nathaniel Lord & Brown, Addison (1913). An Illustrated Flora of the Northern United States, Canada and the British Possessions: From Newfoundland to the Parallel of the Southern Boundary of Virginia, and from the Atlantic Ocean Westward to the 102d Meridian, Volume 3., p. 210. Charles Scribner's Sons, New York.
- "Digital Atlas of the Virginia Flora | Agalinis purpurea (L.) Pennell". Retrieved January 28, 2014. Virginia Botanical Associates. (2014). Digital Atlas of the Virginia Flora (http://www.vaplantatlas.org). c/o Virginia Botanical Associates, Blacksburg.
- "Agalinis - Michigan Flora". Retrieved January 28, 2014. MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan.(http://michiganflora.net)
- Angiosperm Phylogeny Group. 2003. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II. Botanical Journal of the Linnaean Society 141:399-436., cited in Walter Fertig "Farewell to the Aceraceae: Changes in the Angiosperm Family Tree". Retrieved February 8, 2014. The University of Montana Herbarium Newsletter. (Spring 2011). University of Montana, Missoula, MT. http://herbarium.dbs.umt.edu