Carex maolanensis Y.F. Deng & Xi X. Zhang, 2021

Zhang, Xixi, Yao, Zhengming, Meng, Huili & Deng, Yunfei, 2021, Carex maolanensis (Cyperaceae), a new species from Guizhou, China, Phytotaxa 525 (2), pp. 137-146 : 139-143

Carex maolanensis Y.F. Deng & Xi X. Zhang , sp. nov. Figure 2 , 3 .

Diagnosis:—The new species is similar to C. jizhuangensis S. Yun Liang in Dai et al. (2000: 522), but differs by having short rhizome (not long and creeping), 3–7 spikes per node (not single or binate), upper spikes androgynous (not upper 1– 3 male), female glumes awned (not obtuse) at apex, perigynia sparsely hispid (not densely hispid), beak recurved (not suberect).

Type: — CHINA. Guizhou: Libo Xian, Maolan Nature Reserve, Liangshuijing , 107°56’22.29”E, 25°17’33.15”N, 820 m, Limestone hill, in the forest, on the rock, 11 December 2018, Deng Yunfei with Yao Zhengming 27275 (holotype: IBSC) .

Perennial herbs. Rhizome short, woody. Culms densely tufted, 50–80 cm tall, trigonous, smooth, clothed at base with purple or dark brown sheaths. Leaves basal, slightly shorter than culm; blades linear, 2–4 mm wide, leathery, stiff. Lower involucral bracts leaf-like, much longer than inflorescence, upper ones reduced, with sheaths 2–3.5 cm, purple-reddish, upper blades setaceous. Spikes numerous, 3–7 at each node on 6–9 nodes, with peduncles up to 7 cm; terminal one androgynous, 2–3 cm long, male part longer than or equaling female part, male part 1–2 cm long, ca. 1.1 mm wide, female part 1–1.5 cm long, 2–3 mm wide; lower spikes female or mostly with male part at apex, linear-cylindric, ca. 0.5–2 cm long. Male glumes yellow-brown, 2.5–3 mm long, 1.2–1.5 mm wide, midrib green, apex obtuse. Female glumes yellow-brown, oblong, apex acute to obtuse, ca. 2mm long (excluding awn), margins widely whitish, midrib excurrent into a short scabrous awn for 0.5–1.5 mm long. Perigynia yellowish green or turning brown, equaling or longer than glume, oblong-ellipsoid, obtusely trigonous, 3–3.5 mm, sparsely hispidulous, many-veined, base shortly stipitate, apex gradually contracted into a recurved beak for 0.5–0.7 mm long, orifice entire. Achenes tightly enveloped, pale brown, oblong, trigonous, 3–3.5 mm, base curved stipitate, apex abruptly contracted into a beak for ca. 0.5 mm long; stigmas 3.

Distribution and habitat:— Carex maolanensis is known only from Maolan Nature Reserve, Libo Xian, Guizhou Province, China ( Figure 4 ). It grows on the rock in forest on limestone hills at the elevation of 700– 900 m.

Phenology:— Flowering from March to May and fruiting from July to December.

Etymology:— The epithet “ maolanensis ” refers to the type locality of the collection.

Conservation status:— Currently, Carex maolanensis is only known from its type locality, Maolan National Nature Reserve , Libo Xian , Guizhou, China, which is about 300 km 2 in extent and is well protected. It could be assessed to be Endangered ( EN) or Vulnerable ( VU) according to the IUCN Red List criteria ( IUCN 2012). However, for the present, it is better to be classified as Data Deficient ( DD) because there has been no field survey for the populations of the species .

Additional specimens examined (Paratypes): — CHINA. Guizhou: Libo Xian, Maolan Nature Reserve , 12 March 2011, F . L . Chen et al. LB1460 ( IBSC); Libo Xian, Maolan Nature Reserve , 12 March 2011, F . L . Chen et al. LB1465 ( IBSC); Libo Xian, Maolan Nature Reserve, Liangshuijin , 24 March 2010, Y . F . Deng 21618 ( IBSC); Libo Xian, Maolan Nature Reserve , Liangshuijin , 22 April 2019, X.X. Zhang 273 ( IBSC); Libo Xian , Maolan Nature Reserve , Liangshuijin , 740 m, September 27 2021, Y . F . Deng & T . Y . Jiang 30789 ( IBSC) .

Notes:—According to the classification of Ohwi (1936), Carex maolanensis belongs to sect. Decorae. Morphologically, it resembles C. jizhuangensis in having bracts with long and purple-reddish sheath, perigynia hispidulous, many-veined, base shortly stipitate and apex gradually contracted into a short beak, achenes base curved stipitate, apex abruptly contracted into a short beak, but differs by the short rhizome (not long and creeping), 3–7 spikes per node (not single or binate), upper spikes androgynous (not upper 1– 3 male), female glumes with awn at apex (not obtuse), perigynia sparsely hispid (not densely hispid), beak recurved (not suberect) ( Dai et al. 2000, 2010, Deng 2007). Morphological characters compared between C. maolanensis and C. jizhuangensis are shown in table 1. A revised identification key to Chinese species in sect. Decorae is provided below.

Key to the species of Carex sect. Decorae in China

1a. Leaves cauline.

2a. Spikes numerous, 3–5 each rising from involucral bract axil, 1.5–5cm; perigynia olive green, hispidulous above or later glabrous ............................................................................................................................................................................................. C. insignis 2b. Spikes 4–7, 2–4 per node 1–2 cm; perigynia chestnut-brown, glabrous.......................................................................... C. anomoea 1b. Leaves basal, rarely cauline.

3a. Spikes sessile or subsessile, several spikes aggregated in capitate inflorescences .................................................. C. subperakensis 3b. Spikes pedunculate, not forming capitate inflorescences.

4a. Perigynia 4.5–7.5 mm, apex abruptly contracted into long beak more than 1mm.

5a. Spikes all androgynous.

6a. Leaf blades linear, 3–5 mm wide........................................................................................................................................ C. urelytra 6b. Leaf blades broadly linear, 4–12 mm wide.

7a. Style base hispidulous .................................................................................................................................................... C. perakensis 7b. Style base glabrous................................................................................................................................................................. C. morii 5b. Terminal spikes male, remaining spikes androgynous or female.

8a. Style base curved...................................................................................................................................................... C. zhenkangensis 8b. Style base erect....................................................................................................................................................... C. baiposhanensis 4b. Perigynia 2.3–4.5 mm, apex gradually narrowed into rather short beak.

9a. Perigynia ca. 2.3 mm; culms compressed cylindric ........................................................................................................ C. pomiensis 9b. Perigynia 3–4.5 mm; culms trigonous.

10a. Female glumes subequaling to the perigynium; perigynia hispidulous, curved, stipitate

11a. Spikes single or binate per node, terminal ones male; female glumes muticous ...................................................... C. jizhuangensis 11b. Spikes 3–7 per node, terminal ones androgynous; female glumes awned at apex...................................................... C. maolanensis 10b. Female glumes much shorter than the perigynium; perigynia glabrous or sparsely pubescent, contracted at base.

12a. Leaves ca. 2 mm wide ...................................................................................................................................................... C. dielsiana 12b. Leaves less than 1 mm wide............................................................................................................................................ C. barbayaki

Figures

FIGURE 2. Carex maolanensis. A. Habit; B. Inflorescence; C, D. Spikes; E. Female glume; F. Perigynium; G.Achene.

FIGURE 3. Carex maolanensis. A. Habit; B. Abaxial surface of leaf blade; C. Adaxial surface of leaf blade; D–E. Portion of culm; F. Spike; G. Abaxial surface of male glume; H. Adaxial surface of male glume; I. abaxial surface of female glume; J. adaxial surface of female glume; K–L. Perigynium; M. Achene. Drawn from Deng Yunfei with Yao Zhengming 27275 by LIU Yunxiao

FIGURE 4. Distribution map of Carex maolanensis (●).