Arisaema flavum (Forrsskaol) Schott
- genus Arisaema Mart.
Monoecious and male. Tuber subglobose, 1.5-2.5 cm in diameter. Cataphylls 3-5, green, inter 8-25 cm long. Leaves 1-2. Petiole green to purplish, unmarked, 11-35 cm long, 4/5 of the length sheathing in flowering plants, not sheathing in nutritive plants. Leaf blade pedate, leaflets 5-11, green above, glaucous beneath, oblong lanceolate, obovate-lanceolate, acuminate, base cuneate, sessile, central one largest, 9-12 cm long, 3-5 cm wide, outer (lateral leaflets) gradually decreasing to the outermost. Peduncle emerging from leaf-sheath, green, 15-30 cm long. Spathe smallest in the genus, 2.5-6 cm long in total; spate tube yellowish green, ovoid to globes, 1-1.5 cm long, 1-1.4 cm wide, constricted at dark purple throat; limb oblong-ovate, yellow or green, accumulate, inside dark purple at least as basal part, slightly incurved. 1.5-4.5 cm long, 0.8-2 cm wide. Spadix bisexual and male, very short 1-2 cm long in total. Basal part female portion, ovaries greenish congested, obovate, stigma sessile, discoid male portion continued cylindric 3-7 cm long, 2-3 mm thick, light yellow, male flowers congested, synandria usually composed of 2, anthers, anthers 2-loculed, sessile dehiscent by apical pore; appendix very short, yellowish or yellow green, rugose when dry, short ellipsoid, 2-51.5 mm. Mature infructescence erect, subglobose, 4 cm in diameter; berries obovate, seeds 3, pale yellowish, 2-2.5 mm long.
The chromosomal number of Arisaema flavum is 2n = 56 (Murata and Iijima, 1983).
Ecology and Distribution
Flowering from May to June; fruiting from July to October.
Arisaema flavum is occurring in W Sichuan, NW Yunnan, S and SE Xizang of China, NW India, Nepal, Bhutan, Afghanistan, Kashmir.
The evolution of Arisaema is reconstructed, based on combined sequences from the chloroplast trnL intron, trnL-trnF spacer, and rpl20-rps12 spacer (Renner et al., 2004). Sections in Arisaema are mostly based on leaf, stem, and inflorescence characters and, with one exception, are not rejected by the molecular data; however, statistical support for sectional relationships in the genus remains poor. Constraining the age of Arisaema triphyllum to 18 million years (mya) and applying either a semiparametric or an ultrametric clock model to the combined data yields, thus the genus provides an example of the Oligocene/Miocene floristic links between East Africa, Arabia, the Himalayan region, China, and North America. The phylogeny also suggests secondary loss of the environmental sex determination strategy that characterizes all arisaemas except for two subspecies of A. flavum, which have consistently bisexual spathes. These subspecies are tetraploid and capable of selfing, while a third subspecies of A. flavum is diploid and retains the sex-changing strategy. In the molecular trees, the sex-changing subspecies is sister to the two non-sex-changing ones, and the entire species is not basal in the genus.
Growing in rocky slope, thickets, cropland, field sides; 2200-4400 m.
Arisaema flavum is used medically by Tibet people.
- Arum flavum Forsskaol (synonym)
- Arisaema abbreviatum Schott (synonym)
- Arisaema daochengense P. C. Kao (synonym)
- Arisaema flavum subsp. tibeticum J. Murata (synonym)
- Arisaema flavum subsp. abbreviatum (Schott) J. Murata (synonym)