Fargesia purpurea D.Z. Li & X.Y. Ye, 2020

Ye, Xia-Ying, Zhang, Yu-Xiao & Li, De-Zhu, 2020, Two new species of Fargesia (Poaceae, Bambusoideae) from southwestern China, PhytoKeys 170, pp. 25-37 : 25

Fargesia purpurea D.Z. Li & X.Y. Ye sp. nov. Figs 3 , 4 , 5

Diagnosis.

Fargesia purpurea D.Z. Li & X.Y. Ye resembles F. pauciflora (Keng) Yi and F. brevistipedis Yi, but can be distinguished from the former by thinner and taller culms, a ring of 4-5 mm tall brown setae below nodes, glabrous sheath scar, fewer branches and more leaf number, from the latter by a ring of 4-5 mm tall brown setae below nodes, less branch number, glabrous sheath scar, oral setae absent and narrower leaf blade.

Type.

China, Xizang (Tibet), Zayu County, Xiachayu Town, bamboo mountain of new village, 28°31'14"N, 96°57'59"E, 2705 m alt., 24 August 2015, X.Y.Ye & X.He YXY254-1 (holotype & isotype: KUN!).

Description.

Rhizomes pachymorph, rhizome neck 5-10 cm long, 1.2-2 cm in diameter, solid. Culms (3)4-5(6) m tall, unicaespitose, 0.5-1.4 cm in diameter; internodes terete, 30-46 cm long, white powdery and black when culms old, with a ring of 4-5 mm brown setae below nodes, longitudinal ribs prominent; wall 1-4 mm thick, cavity filled with lamellate pith; nodes with weakly prominent supra-nodal ridge; sheath scar prominent, with persistent remains of sheath base. Branches 3-7, open; buds triangular. Shoots purple, or with dark purple spots. Culm sheaths persistent, leathery, narrowly triangular, 1/3 as long as internodes, glabrous, longitudinal ribs prominent, upper margins ciliolate; auricles and oral setae absent; ligule truncate or inclined-truncate, 1-2 mm; blade reflexed, linear-lanceolate, glabrous, narrow than apex of culm sheath, readily deciduous. Foliage leaves 3-5 per ultimate branch; sheaths 2.5-4.5 cm long, glabrous, purple, margins ciliolate; auricles and oral setae absent; ligules truncate, ca. 1 mm; petiole 1-3 mm long; blades lanceolate, 5-12 × 0.5-1.4 cm, abaxially densely white pubescent, base cuneate, secondary veins 3-4 pairs, transverse veins conspicuous, margins serrate. Inflorescence unknown.

Phenology.

New shoots July to August.

Etymology.

The specific epithet refers to the color of culm sheath and leaf sheath.

Vernacular name.

Zǐ Qiào Jiàn Zhú (Chinese pronunciation); 紫鞘箭竹 (Chinese name).

Distribution and habitat.

Fargesia purpurea is only known from the type locality, bamboo mountain of new village in Zayu county. It grows under the evergreen broadleaved forest at an elevation of 2700-2800 m alt.

Additional specimens examined (paratype).

China, Xizang (Tibet), Zayu County, Xiachayu Town, bamboo mountain of new village, 28°32'04"N, 96°59'07"E, 2724 m alt., 24 August 2015, X.Y.Ye & X.He YXY254-2 (KUN!).

Notes.

Morphological comparisons between Fargesia purpurea and the related species were provided in Table 2 . Two species of this genus were distributed in the Zayu county, namely, F. zayuensis Yi and F. macclureana (Bor) Stapleton, with this new species being easily distinguished from them in this region by its glabrous culm sheath and abaxially densely white pubescent leaf blade.

Figures

Figure 3. Fargesia purpurea D. Z. Li & X. Y. Ye A habitat B young and densely white powdery culm with purple culm sheath C individual D rhizome.

Figure 4. Fargesia purpurea D. Z. Li & X. Y. Ye A internodes, showing branches and persistent culm sheath B young culms with culm sheaths C culm bud D branches E node, showing brown setae below node F culm sheath, showing details of blade and ligule G branchlet H leaf sheath I abaxial surface of leaf, showing densely pubescence.

Figure 5. Fargesia purpurea D. Z. Li & X. Y. Ye A internode with branchlet B culm sheath abaxial view, showing culm leaf blade C node with branches D culm bud E yong culm with culm sheath F abaxial surface of leaf, showing densely pubescence.