Carex tsaiana F. T. Wang & Tang ex P. C. Li

Jin, Xiao-Feng, Cen, Jia-Meng, Hahn, Marlene, Lu, Yi-Fei & He, Jin-Jing, 2015, Notes on Carex (Cyperaceae) from China (II): a taxonomic revision of sect. Radicales (Kük.) Nelmes, Phytotaxa 217 (2), pp. 117-132 : 131

(11) Carex tsaiana F. T. Wang & Tang ex P. C. Li (in Li 1999: 169). Type:— CHINA. Yunnan: Pingbian , 18 Jul 1934, H. T. Tsai 60957 (holotype, PE; isotype, IBK!, KUN!) ( Figure 5 : A–E) .

Perennial herbs. Rhizomes short. Culms densely caespitose, 10–20 cm tall, less than 1 mm thick, trigonous. Leaves shorter or equal in length to culms, blades 1–1.5 mm wide, soft, slightly revolute on margins, with persistent dark brown sheaths at base. Involucral bracts leaf-like, shorter than inflorescence. Spike single, androgynous, cylindrical, 10–15 mm, 2–3 mm thick; staminate part of spike slightly shorter than pistillate part. Staminate scales ovate, ca. 3mm long, pale green, acute at apex, green 1-veined costa. Pistillate scales ovate, pale green, 3–3.5 mm long, acute at apex, green 1-veined costa. Perigynia longer than pistillate scales, ellipsoid, trigonous, 4–4.5 mm long, 2-veined laterally and thinly veined, base stipitate at base, ciliate at margins, abruptly contracted into a short beak at apex; orifice 2-lobed with short teeth.Achenes oblong-obovoid, trigonous, brown at maturity, ca. 2.5 mm long, shortly stipitate at base; style thickened at base, conic; stigmas 3.

Additional specimens examined:— CHINA. Yunnan: Yanshan, Gonghua, H. T. Tsai 589116 (IBK).

Note: —This species is similar to Carex daxinensis Y. Y. Zhou & X. F. Jin , but differs by having leaf blades 1–1.5 mm wide, and ellipsoid-shaped perigynia. In Carex daxinensis , the leaves are longer or slightly shorter than culms, the blades are 2–3.5 mm wide, and the perigynia are ellipsoid-ovoid-shaped.

Figures

FIGURE 5. A–E: Carex tsaiana F. T. Wang & Tang ex P. C. Li. (A) habit; (B) staminate scales; (C) pistillate scale; (D) perigynium; (E) achene. F, G: Carex daxinensis Y.Y. Zhou & X. F. Jin. (F) perigynium; (G) achene. H–L: Carex tsoi Merr. & Chun. (H) habit; (I) staminate scales; (J) pistillate scale; (K) perigynium; (L) achene. M–R: Carex planiscapa Chun & How. (M) spike; (N) transverse section of culm; (O) staminate scales; (P) pistillate scale; (Q) perigynium; (R) achene. (A–E drawn from H. T. Tsai 60957 in KUN, F, G from X. F. Jin & Y. Y. Zhou 3026 in HTC, H–L from X. F. Jin 2995 in HTC; M–R from Hainan Exped. 621 in IBK; drawn by Xiao-Feng Jin).