生活型

herb

形態特徵

• Terrestrial herb. Rhizome short, bearing sympodial shoots. Roots fibrous, wiry, smooth, simple or branched, 3-3.5 mm in diameter. Stem 40-45 cm tall, 3.5-5.5 mm in diameter, subterete, rigid, solid, enveloped by leaf sheaths.
• Leaves many, spiral or more or less in 2 rows, glabrous, plicate, elliptic-lanceolate to oblong-lanceolate, 20-28 cm long, 7-9cm broad, caudate-acuminate at apex, contracted and sheathing at base, bearing 7 primary veins, secondary veins between primary veins 1-3, veinlets between primary veins 15-25, sheath 4-4.8 cm long, longitudinally ribbed.
• Inflorescence axillary, erect, paniculate, 5-branched, 10 cm long, 19-flowered, each branch with 2-6 flowers in 2 rows; peduncle 4.5 cm long, with most of its length enveloped by leaf sheath; rachis minutely zigzag; bracts triangular-lanceolate, up to 1 cm long; floral bracts triangular-ovate, cucullate, 4-7 mm long; ovary 6-9 mm long, 6-ribbed, straight or minutely twisted. Flowers non-resupinate, more or less arcuate or minutely twisted and facing varied directions, 20-30 mm long, light yellow-green turning white, scented, the perianth approximate basally, spreading at upper half; sepals subsimilar, independant at base, separated by the ridges of petals and lip, narrowly spathulate, smooth in abaxial side, without ridges, 15-21 mm long, upper half navicular, with inflexed edges, lower half narrowed and grooved; petals as long as the sepals, ridged abaxially, falcate, upper half lunar, flat, arcuate, with undulate margin, lower half narrowed and shallowly grooved; lip 15-21 mm long, ridged abaxially, spathulate, dilated to form a blade at the upper third, contracted and unguiculate below, then slightly dilated and adpressed to the column near the base, blade ovate in outline, crisped and minutely undulate at edges, arcuately deflexed at apex, 6-7 mm by 5-6 mm and rhombic-ovate when flattened, claw divergent to the column, conduplicate and canaliculate, laterally 2-ridged within, ridges most prominent at the middle part of the claw, decreasing their size and becoming inconspicuous towards both ends. Column erect, slender, clavate, 14-18 mm long, dilated and somewhat fusiform at apex, 2.9-3.2 mm wide, bearing 2 auricles at lateral sides, narrowly cylindricle below, auricles triangular; anther 3.1 mm long, 1.1 mm wide, somewhat reniform; stigma 3-lobed, middle lobe occuping the lower half of rostellum, lateral ones deflexed; rostellum long triangular, elongated at apex to form a hamullus.

物候

Flowering period: July to September.

分布

• 台灣 : in mountain forest on western region of the island of Lanyu.

引證標本

Taitung County : Western part of Lanyu, C.L. Yeh & C.R. Yeh 4031(PPI) 19, Aug., 2005.

參考文獻

• Ching-Long Yeh, Chuan-Rong Yeh and Chong-Sheng Leou, Taiwania 51(1): 53. 2006.