Carex fatsuaniana X.F.Jin, Y.F.Lu & Z.C.Lu, 2023

1. Carex fatsuaniana X.F.Jin, Y.F.Lu & Z.C.Lu sp. nov.

Fig. 1A-G View Figure 1

Diagnostic description.

This new species is similar to Carex truncatigluma C.B.Clarke, but differs in having utricles nearly glabrous, nutlets with a ca. 0.5 mm long beak at apex, staminate spikes cylindrical, 5-7.5 cm long, 4-5 mm wide, and pistillate glumes acuminate at apex.

Type.

China. Yunnan: Foo-ning [ Funing County], Ban-loun [Banlun Township], under dense-thickets, alt. 700 m, 10 Apr 1940, C. W. Wang 88293 ( holotype: PE!; isotypes: IBK00181423!, PE!) .

Description.

Perennial herbs. Rhizomes woody, obliquely ascending. Culms lateral, 45-60 cm tall, trigonous, smooth, base with short leaves and brown fibrous sheaths. Leaves longer than culms, blades flat, leathery, 4.5-9 mm wide, scabrous on upper surfaces and margins. Bracts leaf-like or shortly leaf-like, base with 1-2.5 cm long sheath. Spikes 6; terminal spike staminate, cylindrical, 5-7.5 cm long, 4-5 mm wide, base with 8-20 mm long peduncles; lateral spikes pistillate, cylindrical, 2.5-4.5 cm long, 3-3.5 mm wide, densely flowered, with peduncles exserted from or enclosed in sheaths. Staminate glumes elliptic-lanceolate or oblanceolate, pale brown, 7-7.5 mm long, apex acuminate, with 3-veined yellow-brown costa. Pistillate glumes ovate-elliptic or obovate, pale yellow, 2.5-3 mm long, apex acuminate and mucronate, or acute, with 3-veined yellow-brown costa. Utricles yellow-green, narrowly ellipsoid-ovoid, obtusely trigonous, 4-4.5 mm long, longer than pistillate glumes, membranous, obliquely patent, distinctly thinly veined, nearly glabrous, base gradually cuneate, short-stipitate, apex gradually contracted into a ca. 1 mm long beak, orifice 2-lobed with short teeth. Nutlets tightly enveloped, brown, ovoid, trigonous, 2.5-3 mm long, with 3 sides slightly concave below, base short-stipitate, apex contracted into a ca. 0.5 mm long cylindrical beak; style base slightly thickened; stigmas 3.

Etymology.

The specific epithet ' fatsuaniana ' is in honour of Prof. Fa-Tsuan Wang (Fa-Zuan Wang, 1899-1985), the taxonomic founder of Chinese monocots.

Phenology.

Flowering and fruiting occur in early April.

Conservation status.

Data Deficient (DD). Only four sheets ( C. W. Wang 88293) of the new species were collected by Chi-Wu Wang in 1940 from the type locality. Adequate information is lacking on its distribution and population status to make a direct or indirect assessment of the risk of extinction ( IUCN 2019).

Notes.

Carex fatsuaniana has nutlets contracted distally into a ca. 0.5 mm long cylindrical beak at the apex, which morphologically belongs to sect. Carex Lageniformes and is similar to C. truncatigluma ( Dai et al. 2010). In sect. Carex Lageniformes , the species has terminal staminate spikes thinly linear-clavate, whereas those of the new species are cylindrical, 5-7.5 cm long, 4-5 mm wide. The characters distinguishing the new species from C. truncatigluma are shown in Table 1 View Table 1 .

Based on the phylogenetic scaffold for the Carex classification ( Roalson et al. 2021), the sampled species in sect. Carex Lageniformes were arranged in two clades: Carex breviscapa and C. longicolla in Tristachya clade, and Carex truncatigluma in Truncatigluma clade, but C. densipilosa was placed in the uncertain group. The new species, Carex fatsuaniana , is mostly closed to C. truncatigluma in morphology, so it’s temporarily placed in the Truncatigluma clade.