天南星 tian nan xing

Arisaema ambiguum Engler; A. brachyspathum Hayata; A. kwangtungense Merrill; A. limprichtii K. Krause; A. manshuricum Nakai; A. multisectum Engler; A. stenospathum Handel-Mazzetti; A. takeoi Hayata; A. thunbergii Blume var. heterophyllum (Blume) Engler; Heteroarisaema heterophyllum (Blume) Nakai; H. manshuricum (Nakai) Nakai.

Plants monoecious and male. Tuber depressed globose, 2-6 cm in diam. Cataphylls 4 or 5, membranous. Leaf usually solitary; petiole glaucous, 30-60 cm, proximal 3/4 sheathing into pseudostem; leaf blade pedate; leaflets 11-19(-21), shortly petiolulate or sessile, pale greenish abaxially, dull green adaxially, variously shaped, oblanceolate, oblong, or linear-oblong, base cuneate, apex acuminate; central leaflet 3-15 × 0.7-5.8 cm, often much shorter than lateral leaflets; first outer leaflets 7.7-24.2(-31) × (0.7-)2-6.5 cm, gradually smaller to outermost leaflets, distance between leaflets 0.5-5 cm. Peduncle usually longer than petioles, 50-80 cm. Spathe tube glaucous outside, whitish green inside, cylindric, 3.2-8 × 1-2.5 cm, throat slightly recurved; limb strongly incurved, pale greenish to pale yellow abaxially, deep green adaxially, ovate, 2.5-8 × 4-9 cm. Spadix bisexual or male. Bisexual spadix: female zone proximal, 1-2.2 cm; ovary globose; style distinct; stigma punctate; ovules 3 or 4; male zone distal, 1.5-3.2 cm; synandria lax; occasionally with echinate neuter flowers. Male spadix: male zone 3-5 cm × 3-5 mm; synandria stalked, consisting of 2 or 3 anthers, each with 2 thecae dehiscing by apical slits. Appendix ascending, sigmoid, pale whitish, gradually tapering from sessile base to very acute apex, ca. 20 cm, 5-11 mm in diam. at base. Berries yellowish red or red, cylindric, ca. 5 mm. Seed usually 1, clavate. Fl. Apr-May, fr. Jul-Sep.

Forests, thickets, grasslands; below 2700 m. Almost throughout China, except Xizang [Japan, Korea].