Slender plant 60–80 cm tall.Perennating organs subterranean, 3–5 × 3–5 cm, obliquely conical, forming a short chain.Leaves 4–5, the lowest 2 sheath-like, 10–15 × 3.5–4 cm, ovate, acute, the edge undulate.Inflorescence rather laxly many-flowered, the lower capsules formed before the upper flowers open; scape with several sheaths.Pedicel and ovary c. 13 mm long, decurved.Flowers yellow, the lip with purple veins.Sepals erect, obovate, apiculate; dorsal sepal 9 × 4 mm, lateral sepals 10 × 4.5 mm.Petals 9 × 7, obliquely ovate, apiculate, lying over the column.Lip 9 × 6 mm, obscurely 3-lobed near the base, with 2 parallel calli c. 1 mm high in the throat, each branched, with radiating, papillose projections; from the base of each callus a low, verrucose crest runs down the lip.Side lobes rounded, mid-lobe triangular, obtuse; spur conical, short.Column 3 mm long.