Carex daxinensis Y. Y. Zhou & X. F. Jin (2014: 135)

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 : 125

(4) Carex daxinensis Y. Y. Zhou & X. F. Jin (2014: 135) . Type:— CHINA. Guangxi: Daxin, Leiping , 19 May 2013, X. F. Jin & Y. Y. Zhou 3026 (holotype, HTC!; isotype, ZM!) ( Figure 5 : F, G) .

Perennial herbs. Rhizomes short, indurate. Culms loosely caespitose, 10–50 cm tall, 0.5–1 mm thick, trigonous, smooth. Leaves longer to slightly shorter than culms; blades 2–3.5 mm wide, flat, stiff, with dark brown sheaths at base. Involucral bracts leaf-like, nearly equal or slightly shorter than inflorescence, sheathless. Spikes 1–3, androgynous, cylindrical, 10–20 mm long, 3–4 mm wide, densely flowered; staminate part of spike shorter than pistillate part; lateral spikes exserted from middle part of culms, with erect and short peduncles. Staminate scales ovate, ca. 2 mm long, yellowish green, acute at apex, green 1-veined costa. Pistillate scales ovate, ca. 3 mm long, acute at apex, pale green, green 1-veined costa. Perigynia longer than pistillate scales, green, elliposoid-ovoid, compressed trigonous, 4–4.5 mm long, 2-veined laterally and thinly veined, sparsely pubescent at margins, cuneate at base, gradually contracted into a short beak at apex; orifice shortly 2-lobed with minute teeth. Achenes dark brown at maturity, obovoid, compressed trigonous, 2.5–3 mm long, abruptly contracted into a short stipe at base; style slightly thickened at base, trigonous, conic, and sparsely pubescent; stigmas 3.

Additional specimens examined:— CHINA. Guangxi: Daxin, Leiping, X. F. Jin & Y. Y. Zhou 3023 (HTC).

Note:— Carex daxinensis is similar to C. caudispicata in having sparsely pubescent styles, but differs by having ellipsoid-ovoid-shaped perigynia, and having soft leaves that are 2–3.5 mm wide. It is also similar to C. speciosa in having ellipsoid-ovoid-shaped perigynia, soft leaves, and that the staminate part of spike is shorter than pistillate one, but differs in having leaves that are narrower (2–3.5 mm wide), obovoid-shaped achenes, and sparsely pubescent styles.

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).