Lip usually with basal dilation moderately to strongly developed, 5–10 mm; spur slenderly cylindric to slightly clavate, 4–12 mm (± as long as lip, mostly within 2 mm), apex obtuse to tapered; viscidia linear to linear-oblong. 2n = 42.

Flowering May--Aug. Wet meadows, tundra, marshes, fens, stream banks, shores, ditches, seeping slopes, roadsides; 0--3100 m; St. Pierre and Miquelon, Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon; Alaska, Colo., Conn., Idaho, Ill., Ind., Maine, Mass., Mich., Minn., Mont., N.H., N.Mex., N.Y., Oreg., Pa., S.Dak., Utah, Vt., Wash., Wis., Wyo.

Variety dilatata is known in the Northwest Territories only from the extreme southwest, in Nunavut only from some islands in James Bay close to Ontario and Quebec, from New Mexico only from the extreme north-central area, and from South Dakota only from the extreme west.