Peristylus ecalcaratus Finet, Rev. Gén. Bot. 13: 520. 1901; Monorchis ecalcarata (Finet) O. Schwarz.

Plants 10-20 cm tall. Tubers oblong-ovoid, 10-15 × ca. 5 mm. Stem with 2 tubular sheaths at base, 2-leaved. Leaves cauline, widely spaced, alternate, oblong, 10-12 × 0.8-1 cm, apex obtuse. Inflorescence 7-14 cm; peduncle cylindric, with 1-4 ovate-lanceolate sterile bracts 0.2-0.4 cm; rachis 3-8 cm, densely many flowered; floral bracts ovate-lanceolate to lanceolate, ca. 2 mm, shorter than ovary, apex acuminate or acute. Flowers erect or horizontal, white; ovary straight to slightly arcuate, 3-4 mm including pedicel. Dorsal sepal erect, ovate, concave, ca. 1.5 × 1.2 mm, 1-veined, apex obtuse; lateral sepals spreading, ovate, slightly oblique, ca. 1.6 × 1 mm, 1-veined, apex obtuse to subacute. Petals forming a hood to spreading, ovate, slightly oblique, ca. 1.5 × 0.8 mm, 1-veined, apex obtuse; lip obovate, 1.8-2.2 × ca. 1.2 mm, base shallowly concave, apex shallowly 3-lobed; lateral lobes incurved to erect, subtriangular, small, apex obtuse; mid-lobe spreading, broadly ovate, slightly longer and wider than lateral lobes. Column ca. 0.8 mm; anther ca. 0.6 mm; pollinia globose; viscidia elliptic. Fl. Sep.

● Alpine grasslands; 2500-3200 m. W Sichuan, NW Yunnan.