A terrestrial herb 34–50 cm. high, glabrous except for the lip and column-foot. Pseudobulbs fusiform to ovoid, 2–4 cm. long, 1.5 cm. broad, 2-leaved. Leaves ovate-elliptic or elliptic, acute; lamina 6–10 cm. long, (2–)2.5–3.8 cm. broad, spreading, the median nerve prominent on lower surface, dark green with pronounced paler green or white mottling; petiole 3.5–8 cm. long, irregularly articulate. Inflorescence erect, simple, (8–)12–14 cm. long, 3–4 cm. broad, lax or subdense, 8–18-flowered; lower bracts linear-lanceolate, acute; upper bracts triangular-ovate, acute, scarious, shorter than ovary, 2–6 mm. long. Flowers porrect or ± horizontal; sepals olive-green, whitish at base; petals olive-green or yellowish, with plum-purple spots and nerves; middle lobes of lip bright yellow, side lobes cream, with plum-purple nerves, disc white, spotted plum-purple, spur pale green; column green or white, with a plum-purple margin; anther yellow; pedicel and ovary slender, 7–12 mm. long. Dorsal sepal ligulate or narrowly oblanceolate, obtuse, 1-nerved, reflexed, 6–9 mm. long, 2–3.5 mm. broad; lateral sepals ligulate or ± subfalcate, often somewhat spathulate, obtuse, 1-nerved, spreading or deflexed, 7–9 mm. long, 2–2.5 mm. broad. Petals oblong-elliptic, apiculate, 3-nerved, 6.3–8 mm. long, 3.7–4 mm. broad. Lip projecting forwards, articulated at the base, distinctly 3-lobed, with hairs at the base and on the disc, otherwise glabrous, broader than long, 7.5–9 mm. long, 10–12.5 mm. broad; mid-lobe divided into 2 lobules, each flabellate, cuneate at the base, truncate, deflexed, divaricate, margins somewhat erose, nerves inconspicuous, longer than the side lobes; side lobes oblong, rounded, not saccate at the base, erect, nerves prominent; disc minutely papillose, hairy around the callus; basal callus formed of 2 low, rounded, papillose or hirsute, divergent keels, with longer hairs at their base; spur cylindrical, slightly attenuated towards apex, strongly curved outwards towards underside of lip, 2–3(–4) mm. long. Column erect, oblong, 4 mm. long, 2 mm. broad, with a short foot ± 1.5 mm. long; anther ovate, emarginate at apex, 1 mm. long and broad.