Ranunculus aquatilis var. diffusus Withering p.p.  
This name is accepted, but is also synonymized with the following taxa: Ranunculus trichophyllus var. eradicatus, Ranunculus trichophyllus var. trichophyllus
Family: Ranunculaceae
threadleaf crowfoot,  more...
[Ranunculus longirostris Godr.,  more]
Ranunculus aquatilis var. diffusus image
Danielle Walkup & Bill Norris,  
Leaves all filiform-dissected. Achenes 1-1.8 × 0.8-1.2 mm; beak 0.2-1.2 mm. 2 n = 16, 32, 48. Flowering spring-summer (Apr-Sep). Ponds, lakes, streams, ditches, edges of rivers; 0-3200 m; Greenland; Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon; Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., Idaho, Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Mont., Nebr., Nev., N.H., N.Mex., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Mexico; Eurasia; Australia. Populations of Ranunculus aquatilis var. diffusus with long achene beaks are not known from the Old World. In North America, beak length varies continuously over the whole range given for the variety, and separation of plants with unusually long beaks as R . longirostris is not tenable. Ranunculus aquatilis var. diffusus shows geographic variation, and some regional forms have been recognized as separate varieties. Dwarf creeping arctic plants may be called R . aquatilis var. eradicatum , plants with sparsely pubescent or glabrous receptacle from eastern North America may be called R . aquatilis var. calvescens , plants with linear, noncapillary leaf segments from the northern Great Basin may be called R . aquatilis var. porteri , and very robust plants from Oregon and northernmost California may be called R . aquatilis var. harrisii . Extreme forms of these races are recognizable, but they intergrade and many specimens cannot be confidently assigned to one or another of them. The Eurasian species Ranunculus circinatus Sibthorp has been reported from North America. These reports are based on specimens of R . aquatilis var. diffusus .

Stems submersed, elongate, branched; lvs submersed, ternately or binately dissected into filiform segments, relatively firm, not collapsing when withdrawn from water, 1-2 cm, the free petiole none or much shorter than the expanded, pubescent stipular part; fls at the water-surface, white, 1-1.5 cm wide; stamens 10-20; achenes (7-)15-25, with a straight, slender beak 0.7-1.5 mm. Ponds and slow streams; sw. Que. to Del., Tenn., and Ala., w. to Sask., Ida., Nev. and Tex. May-July.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.
Ranunculus aquatilis var. diffusus image
Danielle Walkup & Bill Norris,  
Ranunculus aquatilis var. diffusus image
Danielle Walkup & Bill Norris,  
Ranunculus aquatilis var. diffusus image
Danielle Walkup & Bill Norris,  
Ranunculus aquatilis var. diffusus image
Danielle Walkup & Bill Norris,  
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
. Eastern Nevada Landscape Coalition  
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image
Ranunculus aquatilis var. diffusus image