Arisaema tengtsungense var. pentaphyllum H. Li.

Plants dioecious. Tuber globose, 1-2 cm in diam. Cataphylls 2, whitish pink, short, 2-4 cm, membranous. Leaf solitary; petiole terete, 14-77 cm, basal part forming pseudostem; leaf blade 3-foliolate or rarely quinate; leaflets sessile, pale green abaxially, green adaxially; central leaflet elliptic or ovate-elliptic, 5-14 × 3-7 cm, base cuneate, apex acuminate; lateral leaflets obliquely ovate to ovate-lanceolate, 6-12 × 3-9 cm, base cuneate at inner side, rounded at outer side. Peduncle shorter than petioles, 7-25 cm, emerging from pseudostem. Spathe tube purple with white longitudinal lines, funnel-shaped, ca. 7 × 1.9 cm, throat oblique, not auriculate, slightly recurved; limb dark purple with indistinct whitish lines, galeate, oblong in outline, 5-6.6 × 3-3.5 cm, incurved, apex deeply 3-lobed; middle lobe smaller, lanceolate, ca. 5 × 2 mm; lateral lobes oblong, ca. 1.5 × 1.3 cm, apex rounded. Spadix unisexual; male zone cylindric, 1-1.5 cm; synandria of 2 or 3 stamens; anthers subsessile, globose, dehiscing by horseshoe-shaped slit; appendix pendulous, flagelliform, 8-15 cm, basal 2-3 cm narrowly conic, 2-3.5 mm in diam., base truncate and stipitate; stipe slender, 3-4 mm. Female spadix unknown. Fl. Jun-Jul.

Evergreen forests, Rhododendron thickets on mountain summits; 2600-3200 m. W Yunnan (Jingdong, Lushui, Tengchong) [N Myanmar].