Taiwania, 53(3): 321-323, 2008
Juncus tobdenii Noltie (Juncaceae), a New Record from
Northern Taiwan
Sung-Po Li
(1), Chun-Chi Lin
(2)and Chang-Fu Hsieh
(3,4)(Manuscript received 25 April 2008; accepted 2 June 2008)
ABSTRACT: Juncus tobdenii Noltie, a species distributed in India (Sikkim), has recently been found in northern Taiwan. A full taxonomic description, habitat information and color photographs are provided here.
KEY WORDS: Juncus, Juncaceae, Taxonomy, Taiwan.
INTRODUCTION
The genus Juncus Linn. (Juncaceae), consisting
of about 240 species, is a cosmopolitan genus. It is widely distributed in both hemispheres, especially abundant in cold and temperate regions (Wu and Clemants, 2000). Six species were recorded in the Flora of Taiwan (Kao et al., 2000). One additional species, Juncus tobdenii Noltie, was recently found in northern Taiwan. The first collection of the species in Taiwan was made in 1994 by Mr. Yu-Fa Wang from Yuanyang Lake of northeastern Taiwan. However, this specimen was misidentified as
Rhynchospora alba (L.) Vahl. In year 2000, the
second author collected it again at the same locality. Recently a considerable number of specimens have been collected by the first author from Yuanyang Lake and along the Forest track 160 nearby. This study provides a taxonomic description, note on its distribution and photographs to aid in identification.
TAXONOMIC TREATMENT
Juncus tobdenii Noltie, Edinb. J. Bot. 55(1): 42-43, 1998. 鴛鴦湖燈心草 Figs. 1 & 2 Rhizome creeping, 1.5-2 mm across, condensed. Culms densely tufted; erect, ascending, nodding above to lying down; terete, with a single shallow groove, slender; 39-92 cm long, 0.6-1 mm in diameter; pith continuous. Cataphylls on the base of culm, the lowest ones chaffy, brown and shining, striate, apex short acuminate; the uppermost __________________________________________
1. Sunshine Elementary School, Hsinchu City 300, Taiwan. Email: lisungpo@yahoo.com.tw
2. 77, Mei-Fu Village, Chuang-Wei Hsiang, Ilan 263, Taiwan. 3. Institute of Ecology and Evolutionary Biology, National Taiwan
University, Taipei 106, Taiwan.
4. Corresponding author. Email: tnl@ntu.edu.tw
sheathlike, surrounded at the base of culm, 2.5-10 cm, yellowish brown, apex obliquely truncate, aristate. Inflorescence pseudolateral, anthelate, with 10-30 flowers, lax, branched to 2-3 orders. Involucral bract erect, seemingly a continuation of culm, terete, 8-25 cm long. Bractlets 2, at the base of flower, widely ovate, papery, pale brown, 0.8-1 mm long, about 0.5 mm wide, apex acute to acuminate. Tepals 6, subequal, lanceolate, pale brown, 1.7-2.9 mm long, 0.28-0.6 mm wide, apex attenuate. Stamens 3, filaments about 0.9 mm, anthers about 0.5 mm. Ovary trigonous, about 0.9 mm; style about 0.9 mm, stigmas 3. Capsule ellipsoid, 2.4-2.7 mm long; acuminate at apex, about 0.2-0.3 mm long. Seeds ovate-ellipsoid, 0.48-0.52 mm long, 0.22-0.28 mm wide, yellow-brown, transversely reticulate.
Distribution: India, Sikkim, Yakche (3105 m alt.), Lachen (2743 m alt.), Yakla (3048 m alt.); and Taiwan.
Specimens examined: TAIWAN. Hsinchu County: Yuanyang Lake, 1670 m alt., Y. F. Wang 1033(TAI), C. C. Lin,
s .n. 2000(TNM), S. P. Li 762(TAI, TNM); 160 Forest Road, 1900
m alt., S. P. Li 783(TAI, TNM).
Note: This species was found in the wet places. Some associated herbs included Polygonum
thunbergii Siebold & Zucc., Galium trifidum L., Juncus effuses Linn., Juncus prismatocarpus R.
Brown, Carex capillacea Boott, etc. This species, belonging to subgenus Genuini, is similar to Juncus
effuses Linn.; it can be distinguished from J. effuses
by its slender and single-grooved culms (0.6-1 mm in diameter), and few flowered inflorescence (about 10-30 flowers). On the other hand, J. effuses has stout and erect culums (about 2-2.75 mm in diameter), inflorescence more than 100-150 flowers.
Besides Juncus tobdenii, there are many other species belonging to the eastern Himalaya element in Yuanyang Lake Area, such as the wetland plants
Carex capillacea Boott and Sparganium flallax
322 TAIWANIA Vol. 53, No. 3
Fig. 1. Habit of Juncus tobdenii Noltie in Taiwan (Yuanyang Lake).
Fig. 2. Juncus tobdenii Noltie. A: Inflorescence. B: Ripe fruits.
LITERATURE CITED
Kao, M.-T., C. E. DeVol and T.-C. Huang. 2000. Juncaceae. In: Huang, T.-C. et al. (eds.), Flora of Taiwan, 2nd ed. 5: 147-152. Editorial Committee, Dept. Bot., NTU, Taipei, Taiwan.
Noltie, H. J. 1998. New species of Juncus (Juncaceae) from the Sino-Himalay. Edinb. J. Bot. 55: 39-44.
Wu, G.-F. and S. E. Clemants. 2000. Juncaceae. In: Wu, Z.-Y. and P. H. Raven (eds.), Flora of China
24: 44-69. Science Press, Beijing, and Missouri
Botanical Garden Press, St. Louis, USA.
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