Orchis rotundifolia Banks ex Pursh, Fl. Amer. Sept. 2: 588. 1814; Ponerorchis rotundifolia (Banks ex Pursh) Soó

Plants 7–33 cm. Leaves: blades 2.7–11 × 1.2–8 cm. Inflorescences: floral bracts lanceolate to linear, 5–15 × 1–5 mm, apex acute to acuminate. Flowers showy; sepals white to pale magenta, ovate to elliptic-oblong, 6–10 × 3–4 mm; petals white to pale magenta, ovate to lance-oblong, 5–6 mm, less than 1/2 as wide; lip white, prominently magenta-spotted, rarely with broad, longitudinal, reddish bars, ovate in outline, 6–9 × 4–8 mm, lateral lobes spreading, spur conspicuous, 2/3 as long as to equaling lip, slender. Capsules erect, ellipsoid. 2n = 42.

Flowering Jun--Jul. Moist, often calcareous coniferous forests, thickets, fens, tundra; 0--1200 m; Greenland; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., Nunavut, Ont., Que., Sask., Yukon; Alaska, Maine, Mich., Minn., Mont., N.Y., Vt., Wis., Wyo.