猪笼南星 zhu long nan xing

Arum nepenthoides Wallich, Tent. Fl. Napal. 26. 1824.

Tuber depressed globose, 6-7 cm in diam. Cataphylls, petioles, and peduncle reddish or greenish, densely covered with dark green, dark brown, or black irregular spots consisting of parallel striae. Cataphylls 3, to 25 cm, obtuse at apex. Petiole to 90 cm, basal 10-50 cm sheathing, forming pseudostem; leaf blade digitate; leaflets 5(-7), glaucous abaxially, dull green adaxially, central leaflet with petiolule 2-3 cm, lateral 2 leaflets sessile; central leaflet oblanceolate, 16-20 × 4-5 cm; outermost leaflets 12-14 × 3-4 cm, extremely oblique, narrowly cuneate at inner base, distinctly auriculate semiovate at outer side. Peduncle emerging from pseudostem, shorter or longer than petioles. Spathe tube yellowish with brownish or dark brown spots at both sides, cylindric, 3-8 × 1.2-2.5 cm, throat broadly auriculate, auricles semiorbicular, to 2 cm wide, outcurved; limb arching, yellowish with numerous black spots, triangular-ovate, 3-10 × 2-5 cm, apex acuminate. Spadix unisexual; female zone cylindric, 2-2.5 cm × 8-12 mm; ovaries dense, green, obovoid; stigma yellowish; male zone ca. 1.5 cm; synandria lax; anthers 1-3, violet, shortly stipitate; thecae globose, dehiscing by apical pores. Appendix erect, whitish green, cylindric, 6-8 cm × 4.5-5 mm, base truncate with stipe 5-7 mm, middle part slightly constricted, apex obtuse. Fl. May-Jun. 2n = 26, 26 + 1B.

Tsuga or Quercus forests, forest banks and margins; 2700-3600 m. S Xizang, Yunnan [Bhutan, NE India (Darjeeling, Sikkim), N Myanmar, Nepal].

A Chinese record of Arisaema ochraceum Schott (Lacaita, J. Linn. Soc., Bot. 43: 483. 1916) is referable to A. nepenthoides.