USGS - science for a changing world

Northern Prairie Wildlife Research Center

  Home About NPWRC Our Science Staff Employment Contacts Common Questions About the Site

Aquatic and Wetland Vascular Plants of the Northern Great Plains

9. Ranunculaceae, the Buttercup Family

4. Ranunculus L. -- Buttercup, crowfoot

11. Ranunculus subrigidus W.B. Drew -- White water-crowfoot


Very similar to R. longirostris, occasionally stranded on mud in late summer and assuming a semiterrestrial growth form. Stems usually 2-6 dm long, sometimes over 10 dm long in clear deep water, or only to 1 dm long when stranded, simple or sparingly branched, rooting at the lower nodes. Leaves all cauline or some basal on semiterrestrial forms, the blades finely divided as in R. longirostris, roughly globular in outline, usually 1-3 cm across, often smaller, the filamentous leaf segments flattened on stranded plants; petioles consisting of the stipular leaf bases or extending slightly beyond the dilated base, 2-5 mm long, glabrous or pubescent. Flowers as in R. longirostris. Achenes 30-45(80) in a globose head 3-5 mm long, 3-5 mm thick; achene body obovoid, transversely wrinkled, hispidulous on the back, 1-1.5 mm long, averaging 1.25 mm or less long, the beak 0.2-0.5 mm long (often nearly beakless when dried); receptacle 1-2 mm long, pubescent; peduncles strongly recurved in fruit, (1)3-10 cm long. Jun--Aug. Marshes, lakes, ponds, water-filled ditches and slow-moving streams; common in ND, SD, e MT, WY and perhaps w NE; (Que. to N.W. Terr. and B.C., s to MA, MI, IA, TX, n Mex. and CA). R. circinatus Sibth. var. subrigidus (W. B. Drew) Benson; R. aquatilis L.

The white water-crowfoots, R. longirostris and R. subrigidus, are especially conspicuous in June when the white blossoms may literally cover the water surface of some marshes.

GIF-Ranunculus subrigidus
Ranunculus subrigidus
GIF- Distribution Map

Map key


Previous Species -- Ranunculus sceleratus L. -- Cursed crowfoot
Return to Family -- Ranunculaceae - The Buttercup Family

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/plants/vascplnt/species/ranusubr.htm
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 06:46:26 EST
Sioux Falls, SD [sdww54]