Fimbristylis longquanensis X.F. Jin, Y.F. Lu & C.Z. Zheng, 2017

Lu, Yi-Fei, Zheng, Chao-Zong, Chen, Jian-Min, Ye, Li-Xin, Liu, Sheng-Long & Jin, Xiao-Feng, 2017, Novelties in Fimbristylis (Cyperaceae) from Zhejiang, China: two new species and a new variety, Phytotaxa 309 (2), pp. 127-134 : 130

Fimbristylis longquanensis X.F. Jin, Y.F. Lu & C.Z. Zheng , sp. nov. ( Fig. 1 : A–E; Fig. 2 : A & B).

Haec species Fimbristylo complanatae (Retz.) Link affinis est, sed a qua herbis annuis, rhizomatibus absentibus, bracteis inflorescentiis longioribus vel eis subaequilongis, nuculis laevibus, foliis 2–2.5 mm latis differt.

Type: China. Zhejiang, Longquan County, Guanpuyang, in wet places, elevation 630 m, 27 Aug. 1980, C. F. Zhang, L. X. Hong & B. Y. Ding 5979 (holotype, HTC! ; isotype, PE! ).

Annual herbs. Rhizomes absent. Culms caespitose, acutely trigonous, glabrous, 20–55 cm tall, with 2–4 leaves at base. Leaves shorter than culms; blades 2–2.5 mm wide, flat, acute at apex, slightly scabrous and revolute at upper margin; sheath 1–6 cm long, mouth obliquely split, reddish brown; ligule truncate, shortly ciliolate. Involucral bracts 2, leaf-like, longer or nearly equal to inflorescence; bractlets subulate, 5–15 mm long. Inflorescence simple to decompound anthela, 5–11 × 1.3–7 cm; primary rays 3–6, 1.5–7 cm long. Spikelets 15–45, long-ovoid, acute at apex, 3–6 × 1–2 mm, 7–18-flowered. Scales ovate, reddish brown, 1.8–2 mm long, acuminate or mucronate at apex, narrowly hyaline on margin, with 3 green veins; stamens 2; anthers 2.2–2.5 mm long. Style ca. 1 mm long, thickened to a conical base, glabrous; stigmas 3. Nutlets broadly obovoid, trigonous, pale yellow, smooth, ca. 0.8 mm long, 0.4–0.5 mm in diam., irregularly hexagonal-reticulate. Fl. and fr. in July–September.

Etymology —The specific epithet refers to the type locality, Longquan County.

Paratypes — China. Zhejiang, Longquan County, Guanpuyang, (Cukeng), 119°10’2.55’’E, 27°56’4.36’’N, in wetland near tea farmlands, elevation 720–728 m, 3 Sep. 2016, X. F. Jin, Y. F. Lu, L. X. Ye & S. L. Liu 3843 ( HTC, ZM) , 3844 ( HHBG, HTC) , 3845 ( HTC, PE, ZM) , 3846 ( HTC, PE, ZM) ; Pan’an County, Tianwang, Gaokeng , in farmland, elevation 550 m, 18 August 1988, L. Hong 2407 ( HHBG) ; Wuyi County, Xilian, Shangtian, Mount Niutou , by streams, elevation 400 m, 14 July 1985, C. S. Ding 859140 ( ZJFC) .

Observations —The nutlet shape and surface sculpturing of Fimbristylis longquanensis and F. complanata are shown in Fig. 2 . Both F. longquanensis and F. complanata have the nutlets obovoid, trigonous, stigmas 3, and the epidermal cells are 4–6-gonal. The epidermal cells of F. longquanensis are undulate on the margin, with flat smooth surface, while those of F. complanata are deeply undulate on the margin, with slightly concave surface ( Fig. 2 : D, sample from Lin’an of Zhejiang), or verruculose ( Fig. 2 : F & H, samples from Hangzhou of Zhejiang and Deqing of Guangdong).

Note —The new species is similar to Fimbristylis complanata (Retz.) Link in having stigmas 3 and scales spirally imbricate, but differs from it in being annual herbs, with rhizomes absent, bracts longer than or nearly equal to inflorescence, nutlets smooth, and leaf blades 2–2.5 mm wide. In Fimbristylis complanata , the plants are perennial, with rhizomes short but present, bracts shorter than the inflorescence, nutlets scattered verruculose or smooth, and leaf blades 3–5 mm wide.

Figures

FIGURE 1. Fimbristylis longquanensis X.F. Jin, Y.F. Lu & C.Z. Zheng, sp. nov. (A) habit; (B) opened leaf sheath, showing ciliate ligule; (C) spikelet; (D) scale; (E) nutlet with one stamen (drawn by Xiao-Feng Jin from the holotype).

FIGURE 2. SEM photographs of nutlets. A, B: Fimbristylis longquanensis (from C. F. Zhang & al. 5979 in HTC); C, D: F. complanata (from C. Z. Zheng & C. F. Zhang 5799 in HTC); E, F: F. complanata (from anonymous 1040 in HHBG); G, H: F. complanata (from Y.G. Liu 1213 in HHBG).A, C, E, G: whole view of nutlet (scale bar= 1 mm); B, D, F, H: surface sculpture (scale bar= 100 μm).