Carex yangchunensis X. F. Jin, Y. F. Lu & D. C. Meng, 2025

Carex yangchunensis X. F. Jin, Y. F. Lu & D. C. Meng sp. nov.

Figs 3 A – I View Figure 3 , 4 A – J Chinese name: yáng chūn tái cǎo (阳春薹草 View Figure 4 )

Diagnosis.

This new species is similar to Carex cryptostachys Brongn. , but differs in having spikes 4–8, ovoid or nearly globose, 3–8 mm long (vs. spikes 6–10, cylindrical, 9–25 mm long), utricles 2.5–3.5 mm long (vs. 3.5–4.5 mm long), nutlets 2–2.2 mm long, with styles thickened at base (vs. 2.5–3 mm long, style base not thickened), leaves 3–6 mm wide (vs. 6–16 mm wide) and culms 8–25 cm tall (vs. 10–35 cm tall).

Type.

China, Guangdong (广东), Yangchun County (阳春), Kongdongyan Scenic Spot (崆峒岩景区), from Banshanting to Zhaixingting (半山亭至摘星亭), 22.18544 ° N, 111.74557 ° E, elev. 80 m, 9 April 2024, X. F. Jin & Y. F. Lu 5196 (holotype: ZJFC!; isotypes: IBK!, PE!, ZJFC!, ZM!) GoogleMaps .

Description.

Perennial herbs. Rhizomes elongate, woody, thick. Culms lateral, 8–25 cm tall, compressed-trigonous, slender, smooth, base with dark-brown or brown sheaths, sometimes splitting into fibres. Leaves far longer than culms, apex slender long-caudate; blades 3–6 mm wide, thinly leathery, flat, upper margins and both surfaces scabrous. Bracts short-setaceous, sheathed; sheaths 3–10 mm long, with the most proximal one longer than the others. Spikes 4–8, androgynous, ovoid or nearly globose, 3–8 mm long, base with a 3–17 mm long slender peduncle, staminate part ca. 2 mm long, slightly exserted or hidden in pistillate flowers, pistillate part 3–6 mm long, densely 4–12 - flowered; peduncles exserted from bract sheaths. Staminate glumes ovate, 1.5–2 mm long, yellow-white, obtuse at apex, green 3 - veined dorsal costa. Pistillate glumes obovate or ovate, 2–2.5 mm long, pale yellow-green, acute or obtuse at apex, green 3 - veined dorsal costa. Utricles yellow-green, broadly rhombic-obovoid (excluding beak), obtusely compressed-trigonous, 2.5–3.5 mm long (including beak), longer than pistillate glumes, yellow-green, membranous, distinctly thinly veined, sparsely pubescent on upper dorsal surface and margins, densely pubescent on ventral surface, base cuneate and narrowed into a ca. 0.5 mm long stipe, apex gradually contracted into a ca. 0.3 mm long beak, orifice 2 - lobed with minute teeth. Nutlets tightly enveloped, rhombic-ovoid, trigonous, yellow, 2–2.2 mm long, with 3 angles constricted at middle, sides concave above and below, base with a 0.3–0.7 mm long stipe; style thickened at base, persistent, coiled; stigmas 3.

Etymology.

The specific epithet ‘ yangchunensis ’ refers to the type locality of this new species in Yangchun County.

Phenology.

Flowering and fruiting all the year round.

Distribution and habitat.

The new species has been collected from the limestone regions of Kongdongyan Scenic Spot near Yangchun County, in Heshui and Chunwan townships. It is believed to be distributed in similar limestone hills near Yangchun County. It is currently known to grow on limestone landscapes at lower elevations of 60– 80 m.

Additional specimens examined

(paratypes). China. Guangdong (广东): Yangchun County (阳春), Chunwan Township (春湾镇), Gaocun Tourist Resort (高村旅游度假区), 14 October 2023, D. C. Meng s. n. ( IBK, ZJFC, ZM) ; the same locality, 2 January 2024, D. C. Meng 2024010201 ( ZJFC, ZM) ; Heshui Township (合水镇), Matangjiao Village (麻塘角村), 22.38104 ° N, 111.92091 ° E, elev. 76 m, 8 April 2024, X. F. Jin & Y. F. Lu 5192 ( ZJFC, ZM) GoogleMaps ; Kongdongyan Scenic Spot (崆峒岩景区), Banshanting (半山亭), 22.18571 ° N, 111.74601 ° E, elev. 67 m, 9 April 2024, X. F. Jin & Y. F. Lu 5198 ( PE, ZJFC, ZM) GoogleMaps .

Conservation status.

Least Concern (LC). The new species is a common sedge and grows on cliffs of the limestone regions around Yangchun County, Guangdong Province. Two known populations are in good status, but are strongly influenced by tourist activity, so that the species will need attention at related locations for conservation ( IUCN 2022).