Description from Flora of China
Amomum monophyllum Gagnepain, Bull. Soc. Bot. France 54: 163. 1907.
Bladeless leaves 2. Normal leaves 1(or 2); ligule ca. 2 mm; petiole ca. 14 cm, channeled; leaf blade ovate or oblong, 12--16 × 3--7 cm, leathery, glabrescent, base obliquely acute, apex acute. Inflorescence with flowers in a head; peduncle 1--3 cm; bracts lanceolate, ca. 2 cm; bracteoles ovate, ca. 4 mm. Flowers sessile. Calyx ca. 2.5 cm, apex 3-toothed. Corolla tube ca. 3 cm; lobes ovate-oblong, 1.2--1.5 cm, central one wider than lateral ones, apex cucullate. Lateral staminodes absent. Labellum white with reddish base and yellow middle, orbicular, ca. 1.7 cm in diam., concave, base shortly clawed, apex entire. Filament basally and abaxially pilose; connective appendage subquadrate, entire, ca. 4 mm, concave. Ovary slightly pilose, inconspicuously 6-angled. Fl. May.
Forest floors; near sea level to 100 m. Hainan [Laos].