Arisaema menghaiense J.T.Yin, H.Li & Z.F.Xu

Perennial, dioecious, herbaceous epiphyte; tuber depressed-globose, ca. 5 x 10 cm, renewing seasonally, purple outside with brown spots, 1-1.5 mm diam.; roots whitish, 2-7 cm long, 1-2 mm diam. Leaf (from fruiting plant) 1; petiole cylindrical, green and smooth without spots, 20-30 cm long, ca. 1 cm diam.; leaf blade greenish, membranaceous, trifoliolate; leaflets petiolulate; terminal leaflet ovate, ca. 20 x 10 cm; apex acute; base cuneate, lateral veins numerous, connective vein 2-3 mm remote from the margin, petiolule 15 mm long; lateral leaflets obliquely ovate-lanceolate, ca. 21 x 8 cm; apex acuminate with 5-8 mm filiform tail; base obliquely cuneate; petiolules 8-11 mm long. Inflorescences unisexual, appearing before the leaf; cataphylls 3, membranaceous, pale green, oblong; apex obtuse, 18-23 cm long; peduncle terete, white, ca. 26 x 0.3 cm (male), 25 x 1 cm (female); male spathe tube cylindrical, green, ca. 6 x 1.5 cm, throat margin broadly auriculate, strongly outward recurved; limb greenish purple, ovate-lanceolate, arched, ca. 6 x 5 cm, apex acuminate with a purple tail up to 60 cm long; female spathe tube whitish green, cylindrical, slightly constricted near the throat, ca. 5 x 1 cm; throat obliquely truncate; limb erect, whitish green, ovate-lanceolate, ca. 4 x 3.5 cm; apex acuminate, with a greenish tail up to 25 cm long. Male spadix with basal fertile portion cylindrical, ca. 3.8 x 0.5-0.6 cm, densely flowered; synandria subsessile, purple; anthers 4 to 6, subglobose, dehiscing by an apical slit; appendix sessile, cylindrical, greenish, ca. 3.8 x 0.3 cm; apex obtuse, with a few subulate neuter flowers in lower part; female spadix with basal portion cylindrical, ca. 2.2 x 0.8 cm, densely flowered; ovaries green, 1-loculed, ovoid; stigmas subsessile, discoid; ovules 5 to 6, basal, erect; appendix as in male spadix. Fruiting spadix cylindrical, ca. 5.2 x 1-1.5 cm; appendix ca. 4.5 cm long.