Annual herb, usually branched from the base, glabrous to sparsely pilose, up to 15 cm tall. Leaves are entire or with few remote teeth, alternate and amplexicaul, lanceolate in shape, gradually narrowing into a vaginate, multicostate petiole, up to 14 cm long and 17 mm wide. Scapes are axillary and up to 20 cm long. Spikes are dense and ovoid, 0.5–3 cm long. Bracts are ovate-oblong, glabrous, with a green median band and wide scarious margins, up to 6 mm long and wide. Sepals are broadly ovate, also with a green median band and wide scarious margins. Corolla tube is glabrous and enclosed by the bracts and calyx; the corolla lobes are lanceolate, white and membranous, with a prominent brown triangular patch at the base. Fruits are ellipsoid capsules, about 6 mm long and 4 mm wide, with a brown, membranous base and a greenish-white lid. Seeds are borne in pairs, dark greenish-brown, strongly concave, 6 mm long and 3 mm wide.