Carex damingshanica Z.C.Lu & X.F.Jin, 2023

Lu, Yi-Fei, Lu, Zhao-Cen, Duan, Yu-Hao, Zhang, Kun & Jin, Xiao-Feng, 2023, Notes on Carex (Cyperaceae) from China (IX): three new species of section Mitratae s. l., PhytoKeys 225, pp. 153-164 : 153

2. Carex damingshanica Z.C.Lu & X.F.Jin sp. nov.

Figs 2A-G , 3A-H

Diagnostic description.

This new species is similar to Carex breviscapa C.B.Clarke and C. rhynchachaenium C.B.Clarke in having spikes in a short racemose and culms much shorter than leaves, but differs from these two relatives in having spikes 3 or 4, lateral spikes cylindrical, shorter, 4-11 mm long, pistillate glumes (1-1.2 mm long), utricles (2.5-3 mm long) and nutlets (1.5-1.9 mm long) all shorter than in related species.

Type.

China. Guangxi: Nanning City, Shanglin County, Dafeng Town , Shuiyuan Village , Damingshan , 23°24'53.29"N, 108°31'45.16"E, under broad-leaved forest, alt. 423 m, 26 May 2020, P. Yang et al. 450125200526074LY (holotype: ZM!; isotypes: IBK00445399!, IBK00445400!, ZJFC!, ZM!) .

Description.

Perennial herbs. Rhizomes short, woody, stiff. Culms central, loosely turfed, 2.5-11 cm tall, trigonous, base with brown fibrous sheaths. Leaves much longer than culms, blades 1.5-3.5 mm wide, flat, leathery, scabrous on upper part and margins. Lowermost bract leaf-like, longer than inflorescence, base with 1-2 mm long sheath or sheathless, others setaceous, shorter than inflorescence, sheathless. Spikes 3 or 4, aggregated; terminal spike staminate, narrowly linear-cylindrical, 6-20 mm long, 1-1.5 mm wide, base with 1-3 mm long peduncles; lateral spikes pistillate, cylindrical, 4-13 mm long, 2.5-3 mm wide, loosely 9-14-flowered, with peduncles slightly exserted from sheaths. Staminate glumes broadly ovate, pale yellow-brown, ca. 1.5 mm long, apex obtuse, with 3-veined yellow costa. Pistillate glumes ovate, pale yellow, 1-1.2 mm long, apex acuminate, with 3-veined yellow costa. Utricles yellow-green, narrowly fusiform, obtusely trigonous, 2.5-3 mm long, longer than pistillate glumes, membranous, obliquely patent, distinctly thinly veined, sparsely pubescent, base gradually cuneate, short-stipitate, apex gradually contracted into a ca. 0.5 mm long beak, orifice 2-lobed with minute teeth. Nutlets tightly enveloped, brown, narrowly ovoid, trigonous, 1.5-1.9 mm long, with 3 sides slightly concave above and below, base with a ca. 0.2 mm long stipe, apex contracted into a 0.2-0.4 mm long cylindrical beak, truncate and shallowly concave at top; style base slightly thickened; stigmas 3.

Etymology.

The specific epithet ' damingshanica ' refers to the type locality of this new species.

Phenology.

Flowering and fruiting occur from late March to late May.

Additional specimens examined.

China. Guangxi: Nanning City, Shanglin County, Xiyan Town , Jianglu Village , Damingshan , from Zuitun to Sanbao , 23°30'50.83"N, 108°28'22.42"E, under broad-leaved forest, alt. 473 m, 31 May 2020, Y. L. Su et al. 450125200531038LY (IBK00445401!, IBK00445402!, ZJFC!, ZM!); Nanning City, Shanglin County , Dalan River , Damingshan, alt. 460 m, 16 Oct 2011, L. Wu & J. C. Yang D3254 (IBK00218552!); Nanning City, Shanglin County , Liangjiang Town , Chaoyang River , Damingshan, alt. 1030 m, 23 May 2011, L. Wu D2120 (IBK00218553!) .

Conservation status.

Least Concern (LC). The new species is known from four localities in Damingshan National Nature Reserve of Guangxi. These populations are in protected areas where they are not really threatened but need attention at ordinary times ( IUCN 2019).

Notes.

Carex damingshanica belongs to sect. Carex Lageniformes in having terminal spikes staminate and nutlets apex contracted into a prominent long cylindrical beak ( Dai et al. 2010). It is similar to C. breviscapa and C. rhynchachaenium , but differs from these two species in the characters of spikes, pistillate glumes, utricles and nutlets. The morphological differences of C. damingshanica , C. breviscapa and C. rhynchachaenium are shown in Table 2 .

As above-mentioned, Carex breviscapa was placed in Tristachya clade, therefore its closed species, C. damingshanica , is temporarily placed in the Tristachya clade.

Figures

Figure 2. Carex damingshanica sp. nov. A habit B upper part of inflorescence C staminate glume D pistillate glume E utricle F nutlet. (Drawn by Xiao-Feng Jin; based on the holotype: P. Yang et al. 450125200526074 LY in ZM).

Figure 3. Carex damingshanica sp. nov. A, B habit C nutlets D pistillate glume E inflorescence F pistillate spike G staminate spike H utricle. (C, D, F-H from type material).