Rhizomes deep purple-red inside. Pseudostems 60--100 cm. Leaf sheath brown; ligule 2-lobed, 1--3 cm, brown pubescent; petiole 1--9 cm; leaf blade elliptic or elliptic-lanceolate, 40--55 × 14--16 cm, adaxially sparsely hairy, abaxially densely pubescent, base cuneate or attenuate, margin ciliate, apex shortly acuminate. Inflorescences breaking through leaf sheaths 20--50 cm above ground, sessile, ellipsoid to oblong, 11--18 × 4--5.5 cm; bracts yellowish white or pale yellowish green, obovate, 4--4.5 × 3--4.5 cm, pubescent, copiously slimy. Calyx yellowish, 1.5--2 cm, split on 1 side, pubescent. Corolla tube yellowish, 4--4.5 cm; central lobe narrowly ovate, 2--3 cm × 8--10 mm; lateral lobes lanceolate, 5--7 mm wide. Labellum 2.4--2.8 cm; central lobe purple with 2 parallel, yellow lines and yellow blotches at base, obovate-oblong, 1.5--2 cm × 7--9 mm; lateral lobes yellow with purple blotches, elliptic, 1.2--1.6 cm × 6--8 mm. Filament 5--10 mm; anther yellow, 1.3--1.4 cm; connective appendage purple, 1--1.3 cm. Ovary glabrous. Capsule yellow-green, obovoid, 3-angled, apex with persistent calyx. Seeds 4--6 per valve, brownish black, enclosed by white aril. Fl. Aug, fr. Oct. 2 n = 22*.