10. Arisaema petiolulatum J. D. Hooker, Fl. Brit. India. 6: 498. 1894.
三匹箭 san pi jian
Arisaema inkiangense H. Li; A. inkiangense var. maculatum H. Li.
Plants monoecious and male, evergreen. Rhizome pale yellow outside, purple or violet in section, cylindric. Cataphylls withering, yellowish red to creamy red, narrowly lanceolate, membranous. Leaf 1; petiole encircled by cataphylls, pale, unspotted, to 40 cm, base sheathing for ca. 1.5 cm; leaf blade pale green abaxially, green adaxially, papery, 3-foliolate; central leaflet with petiolule ca. 2 cm, blade elliptic, 9-25 × 5.8-10 cm, base obtuse or shortly cuneate, apex acuminate; lateral leaflets with petiolule 5-10 mm, blade elliptic-lanceolate, 8-20 × 3.5-9.5 cm, base obliquely rounded. Peduncle encircled by 2 cataphylls, separated from petiole, terete, 25-35 × 1.2-1.5 cm. Spathe tube greenish white, with ca. 1 cm white base, ca. 5 cm × 8 mm, throat margin narrowly auriculate, outwardly recurved, auricle ca. 8 mm wide; limb arching, green with a large rounded white area at base, ovate-lanceolate, ca. 6 × 3 cm, membranous, with a tail ca. 5 mm. Spadix bisexual in mature plants, unisexual (male) in small plants. Bisexual spadix: basal female zone cylindric, ca. 1.5 cm, ca. 5 mm in diam. at base, densely flowered; ovary oblong; ovules 2-4, basal, erect; style short but distinct; stigma capitate, pilosulose; continual male zone ca. 1.5 cm with sparse male flowers; synandria of 2 or 3 stamens; anthers sessile, or filaments ca. 1 mm; thecae subglobose, opening by an apical slit; appendix erect, sessile, green, narrowly cylindric, without neuter flowers, distally slightly rugose. Unisexual spadix: male zone ca. 2 cm, ca. 3.5 mm in diam. with a stipe ca. 2 mm; appendix as in bisexual spadix, with or without 2 or 3 subulate neuter flowers in proximal part. Fl. Oct-Nov.
Dense forests, in mountain valleys; 400-1700 m. Yunnan [NE India, N Myanmar].