North American white adder’s-mouth, malaxis à pédicelles courts

Microstylis brachypoda A. Gray, Ann. Lyceum Nat. Hist. New York 3: 228. 1835; Malaxis brachypoda (A. Gray) Fernald

Plants 3–30 cm. Pseudobulbs 4–8 mm diam. Leaves 1(–2, rarely), petiolate base sheathing stem; blade light green, ovate-elliptic, keeled abaxially, 1.5–9.5 × 1–5 cm, apex acute. Inflorescences: floral bracts lanceolate, 1.5–2 mm; pedicels 2–4.5 mm. Flowers resupinate, green or greenish white; dorsal sepal ovate-lanceolate, 1.5–2.5 × 1–1.4 mm, margins revolute, apex acuminate; lateral sepals oblong-lanceolate, slightly falcate, 1.5–2.5 × 0.5–1.2 mm, apex acuminate; petals strongly reflexed, filiform to narrowly linear-lanceolate, 1.4–2.5 × 0.3–0.4 (–0.5) mm, apex rounded; lip broadly triangular, concave, 3-lobed, middle lobe ovate, apex acuminate, lateral lobes auriculate, thickened, curved upward; disc with 2 low, thickened, elongate calli, 1.3–2.2 × 1.2–1.8(–2) mm; column 0.4–0.6 × 0.4–0.6 mm. 2n = 28.

Flowering summer. Swamps, bogs; 0--400 m; Alta., B.C., Man., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que., Sask., Yukon; Alaska, Calif., Colo., Ill., Ind., Maine, Mass., Minn., N.H., N.Y., Pa., Vt., Wis.