台東龍膽

Gentiana squarrosa auct. non Ledeb. (1812): Kitamura, Acta Phytotax. Geobot. 10: 183. 1941; Ying, Quart. J. Exp. Forest N. T. U. 3(2): 95. 1989. Gentiana yokusai auct. non Burk. (1906): Ho, Fl. Reipubl. Popularis Sin. 62: 234. 1988; Ho & Pringle in Wu et al., Fl. China 16: 78. 1995.

Annual herbs. Stems usually branched, yellowish green, caespitose glabrous, 6-8 cm tall. Leaves aristate-acuminate at apices, slightly scabrous along margins; radical leaves lanceolate or ovate, 7-8 mm long, 4-5 mm wide; cauline leaves lanceolate to narrow-ovate, about 5 mm long, 3 mm wide; sheaths 1-2 mm long. Flowers pedicellate, solitary on terminal branches; pedicels 2-6 mm long; calyx-tube campanulate, 2-3 mm long, with 4 or 5 scabrous costae, 4 or 5-lobed, broadly ovate, aristate-acuminate at apex, about 2 mm long, the lobes with erose costae, minute aculeus along margins; corolla tubular-campanulate, light blue, with brown bands or spots in the middle, about 7 mm long, with 4 or 5 lobes; the lobes acutely ovate, 1-2 mm long, aristate-acuminate at apices, sinuses plicate with ovate-triangular appendages, the appendages acute or cuspidate near apices; stamens 4 or 5, the anthers oblong, 0.4-0.6 mm long, the filaments about 3-4 mm long, attached slightly above the lower-part of corolla-tube; ovary shortly stipitate, lanceolate to narrow ovate, 2-3 mm long, about 1 mm wide, stipe 1 mm long, style about 1 mm long, stigmas bifurcate and spirally recurved at bloom. Capsules obovoid, about 4 mm long, 3 mm wide, stipe 3-6 mm long, 2-valved, dehiscent, the valves denticulate along margin. Seeds ovoid, with minutely longitudinal reticulate-striae, 0.5-0.6 mm long, 0.3-0.4 mm wide.

TYPE: Prof.. Hualien: Wuchuancheng, T. Kawakami s. n. Apr., 1907. (holotype: TI!; isotype: TAIF!）.

ILAN HSIEN: Tungao, elev. ca. 100m, Huang 3706 (TAI). HUALIEN HSIEN: Loshao, elev. ca. 1900-2100m, C. H. Chen 1603 (TNU); Yenhailintao, elev. ca. 650-1200m, C. H. Chen 1195; same loc., elev. ca. 650-1200m, C. H. Chen 1196 (TNU); same loc., Wang 6807 (TNU); same loc., Wang 7664 (TNU); Wuchuancheng, T. Kawakami s. n. Apr., 1907 (TAIF).

Distribution and habitat. Endemic to Taiwan, distributed on semishady grasslands or roadsides in northeast part of Taiwan. At mountain range from 50 to 2,100 m in elevation. Flowering and fruiting Mar-Jun.

Notes. Resembling Gentiana tentyoensis, G. tenuissima is quite different from remainder species distributed in the central and the west part of Central Mountain Range in Taiwan. Ho (1988) compared the G. yokusai distributed in Mainland China with G. tenuissima of Taiwan, and found that the two species differ in sizes of plants, flowers and leaves only. Thus, she treated these two as the same species. Therefore, taking consideration of the original description and some specimens of G. yokusai and G. tenuissima, the plant size and flowers of G. tenuissima exhibit stable size-range and obviously smaller than those of G. yokusai. Besides, that G. tenuissima is sometimes 4-numeral on flowers can be used to distinguish them.