A Taxonomic Study on Dioscorea of Taiwan － Dioscorea collettii
山羊百科，林文智老師的植物、山岳、攝影紀錄
- Chun Kuei Liao chunkuei.liao@gmail.com 2000/06
6. Dioscorea collettii Hooker f. in Fl. Brit. Ind. 6:290. 1894; Knuth in Engl. Pflanzenr. 87(4-43):253. 1924; Yamamoto, Suppl. Icon. Pl. Formos. 3:6. 1927; Sasaki, List Pl. Formos. 114. 1928; Nemoto, Fl. Jap. Suppl. 1084. 1936; Liu, T. S. & T. C. Huang in Bot. Bull. Acad. Sin. 3(2):148. 1962; Liu, T. S. & T. C. Huang in Fl. Taiwan 5:104. 1978; Ting, C. T., M. C. Chang & P. P. Ling. in Fl. China 16(1):69, f.19. 1985.
－Dioscorea kaoi Liu & Huang in Taiwania 7:33. 1960; Liu, T. S. & T. C. Huang in Bot. Bull. Acad. Sin. 3(2):147. 1962; Liu, T. S. & T. C. Huang in Fl. Taiwan 5:108. 1978; Ting, C. T., M. C. Chang & P. P. Ling. in Fl. China 16(1):72, f.19. 1985(p.p.).
－Dioscorea kelungensis Hayata, Icon. Pl. Formos. 10:36, f.19. 1921.
－Dioscorea tashiroi Hayata, Icon. Pl. Formos. 10:44, f.28.1921.
HABIT DESCRIBE
A glabrous scandent vine shooting from a corm-like structure perennial rhizome; underground horizontal rhizome ginger-like, ca. 2 cm in cross-section, branched, with slender roots; flesh yellow, poisonous; aerial stems annual, slender, sinistrose, terete, ca. 1-3 mm thick, green, sometimes with setulose at base of stems; aerial tuber never existed. Leaves alternate, green, black in dry, membranous, ovate-triangular, oblong-ovate, ca. 7-10 (19) cm long, ca. 4-6 (14) cm wide, acuminate or caudate at apex, 3-7 slightly lobed and undulate at margin, auriculate or cordate at base, nerves 7, convex on lower surface; petioles slender, dilated and bearing 2 stipuliform spines.
Staminate inflorescence spicate, axillary, slender, 1-2 together, ca. 5-15 cm long, or compound to panicliform. Male flowers sessile, discordial, 3-7 fascicled on rachis; fasiculate-unit bearing a bract which ovate ca. 1.7 mm long, ca. 1 mm wide, acuminate at apex, irregular dentate at margin, round at base; male flowers with 2-bracteoles; outer bracteole orbucular, ca. 1 mm in diameter, irregular-lobed at margin; inner bracteole similar to outer one, ca. 0.8 mm in diameter; perianth-segments 6, subequal, thickened at central part, green; outer 3 perianth-segments, deltoid, ca. 0.8 mm long, 1 mm wide, acute at apex; inner 3 perianth-segments, oblong, ca. 1.1 mm long, 0.8 mm wide, obtus at apex; stamens 3, filaments, ca. 0.5 mm long, ca. 0.1 mm thick, binate at apex and bearing 2-sticked gland on the divaricate, insert at base of outer perianth-segments, anthers, elliptic, ca. 0.2 mm long, ca. 0.1 mm wide, dorsifixed, longitudinally dehiscent, 2-celled, staminodia 3, stick-like, ca. 0.5 mm long, ca. 0.2 mm thick, slightly binate at apex, alternate to stamens, inserted on base of inner perianth-segments; pistillodium rudimentary; stigmatiform 3, conicus, ca. 0.3 mm tall. Pistillate inflorescence, spicate, axillary, 1-2 together, slender, ca.10-15 cm long; rachis triangular, ca. 1 mm thick. Female flowers green, solitary, ca. 5 mm long, ca. 1.3 mm wide, 2-bracted; outer bract ovate, ca. 1.1 mm long, ca. 0.8 mm wide, acute at apex, slightly dentate at margin, round at base, thickened at central; inner bract widely ovate, ca. 0.9 mm long, ca. 0.8 mm wide, acute at apex, dentate at margin, round at base, thickened on central part; perianth-segments similar to male flowers; staminodia 6, inserted at base of perianth-segments; outer 3 staminodia with 4-nippled gland on a round base, ca. 0.2 mm tall; inner 3 staminodia stick-like, ca. 0.2 mm lomg, binate at apex; stigmas 3, ca. 0.3 mm tall, 2-cleft at apex; ovary inferior, trigonous, 3-celled, with 2-anatropus ovules; pedicles short and reflexed after pollination. Fruit capsulate, tripterous, depressed-obovate, cuneiforms, obcordate, ca. 1.5-2 cm long, ca. 2.2-3 cm wide, truncate or retuse at apex; obtude or round at base, herberous, green, brown in dry, dehiscent at apex only; stiple reflexed. Seeds 2 in each cell, flattened-orbicular, ca. 4 mm in diameter, brown, with membranous wing around; wing ca. 5 mm broad.
Distributed in Taiwan, China, India and Bruma. This species is common in thicket and roadside thoughtout Taiwan, Lanyu and Lutao, from low to 2,000m in altitude.
This species is flowering from February to November, and fruiting from March to November.
SPECIMENS EXAMINED
SPECIMENS EXAMINED. Taipei City: Nankangshan, C. I. Peng 6408 (HAST); Yanminshan, C. K. Liou et al. 458 (HAST), J. Panero et al. 6402 (HAST). Taipei Hsien: Keelung city,S. Sasaki & S. Yujis s.n. (TFRI 6237), B. Hayata & S. Sasaki in 1912 (TFRI 6238); Pinlin, Y. P. Yang & B. L. Shih s.n. in 1977 (TFRI 51313); Shifenliao, S. C. Hsiao 1297 (HAST); Tsaolingkudau, C. K. Liou 198 (TFRI). Taoyuan Hsien: Litunshan, M. T. Kao 10205 (TAI). Hsinchu Hsien: Nalo (Chienshih Hsiang), Y. C. Lu 1524, 1525 (HAST). Taichung Hsien: Lishan, C. I. Peng 6285 (HAST), T. Y. Aleck Yang 6408 (HAST). Nantou Hsien: Fenghuangshan (Luku Hsiang), H. L. Ho et al. 776 (HAST); Meifeng, J. C. Wang et al. 10111 (HAST), S. H. Wu 156 (HAST); Shouting, C. I. Peng et al. 10849 (HAST); Wanta, U. Mori s.n. in 1909 (TFRI 6245). Chiayi Hsien: Chishinliao, H. F. Yen & M. T. Kao 10729 (TAI). Kaohsiung Hsien: Tengchih (Taoyuan Hsiang), Y. K. Chen 595 (HAST); Meilan logging road (Taiyuan Hsiang), T. Y. Liu et al. 421 (HAST). Kaohsiung City: Nanjenshan, C. I. Peng 5509, 5510 (HAST). Pingtung Hsien: Chihpen logging road (Peinan Hsiang), C. M. Wang et al. 1608 (HAST). Taitung Hsien: Chihpen, H. P. Tseng s.n. in 1989 (PPI 40319). Lutao: C. C. Chen 86, 93 (PPI); C. E. Chang 14531, 15980, 18971 (PPI). Lanyu: C. I. Peng 7658 (HAST), C. E. Chang 6179, 6227, 7797, 9208, 18245, 18409 (PPI), S. Sasaki s.n. in 1912 (TFRI 6221); Chingsheishan, C. E. Chang 11424, 11425 (PPI); Honhtou, C. C. Liao et al. 1154 (HAST); Hongtoushan, C. E. Chang 19799 (PPI); Hongtou-Tienchi, C. I. Peng 5238 (HAST), W. P. Leu 1371 (HAST); Jungaih Bridge, J. C. Wang et al. 6019 (HAST), T. Y. Aleck Yang et al. 7737 (HAST); Langtao, C. E. Chang 14732 (PPI); Tasenshan, C. I. Peng et al. 10802, 10803 (HAST), C. E. Chang 19675 (PPI); Teintsiu, C. E. Chang s.n. in 1972 (PPI 1128), T. G. Lammers 8536 (HAST); Tungching-Hongtoushan, C. I. Peng et al. 10677 (HAST); Yehyu, T. Y. Yang 6659 (HAST); Yujenhsi-Hungtoushan, C. I. Peng 6620, 6647 (HAST). Hualien Hsien: Chingshuishan, C. I. Peng et al. 10677 (HAST); Jinnherng Bridge, C. I. Chang 9309 (HAST); Luming-Lanshan (Chosi Hsiang), C. I. Peng et al. 11699 (HAST); Nanan-Huangma (Chosi Hsiang), L. Y. Lin 61 (HAST); Tali-Tatung (Hsinlin Hsiang), C. H. Chen 1686 (HAST); Tsankung Temple, C. I. Peng et al. 12325 (HAST);
