Youngia baoxingensis Y. S. Chen, 2018

Chen, You-Sheng, 2018, Youngia baoxingensis, a new species of Asteraceae (tribe Cichorieae) from Sichuan, China, Phytotaxa 382 (2), pp. 239-242 : 241

Youngia baoxingensis Y. S. Chen , sp. nov. ( Figs. 1 & 2 )

Type:— CHINA. Sichuan: Baoxing county, Longdong Xiang, Ganyanggou , 30°26’36.24”N, 102°29’52.8”E, grassy slope in ravine, 2940– 3200 m, 5 August 2007, Y. S. Chen 7280 (holotype PE ; isotype PE ).

Herbs perennial, 18–30 cm tall, glabrous, with rhizomate rootstock bearing fleshy fibrous roots; caudex short, leafy. Caudical leaves 6–8, ascending, blade oblong, 3–7 × 0.8–1.4 cm, margin remotely denticulate to subentire, apex acute, base cuneate, glabrous on both surfaces, petioles 2–3 cm; cauline leaves 2–3, linear, bract-like, borne at the base of branchlets. Stem erect, slender, glabrous, branched above middle. Synflorescence corymbiform; capitula (3–)10–15; peduncles very slender, 1–2 cm, glabrous. Involucres cylindrical, 3–5 mm in diameter, 9–10 mm high, glabrous; outer phyllaries ca. 5, ovate, dark green, 1–1.5 × ca. 1 mm; inner phyllaries 5–7, lanceolate, nearly equal, 9–10 × 1.5–2 mm, dark green, scarious-margined, crested with a narrow curved claw near tip; florets 6–7, ligules ca. 10 × 4 mm, 5-toothed, teeth 0.5–0.6 mm, tube 3–4 mm; anther tube ca. 4 mm; style branches ca. 1 mm. Achene blackish brown, fusiform, ca. 4 × 0.3 mm, compressed, strongly attenuate to the narrow neck, with conical summit, 12–14-ribbed. Pappus brown, 4–6 mm, 1-seriate, persistent.

Distribution and habitat:— Youngia baoxingensis is currently known only from its type locality, i.e. Baoxing county, Sichuan province, China. It grows on grassy slopes at the margins of mixed forests in a ravine at elevations of 2950–3200 m.

Phenology:—Flowering and fruiting from August to September.

Etymology:—The epithet indicates the type locality, i.e. Baoxing county, Sichuan province, China.

Discussion:— Youngia baoxingensis , characterized by small, 6–7-flowered heads and outer phyllaries ca. 1/9 as long as inner ones and achenes ca. 4 mm long, belongs to Youngia sect. Mesomeris Babcock & Stebbins (1937: 26) . In general appearance it is similar to Y. yilingii Shih (1995: 181) , but distinct by its oblong and entire (vs. spathulate, elliptic or oblanceolate, more or less pinnatifid) leaf blade, brownish (vs. white) pappus, and 6–7 (vs. 9–15) florets.

Figures

FIGURE 1. Youngia baoxingensis Y. S. Chen, sp. nov. (Y. S. Chen 7280). A. Living plant in the wild; B. Capitulum in front view; C. Capitulum in later view.

FIGURE 2. Youngia baoxingensis Y. S. Chen, sp. nov.A. Habit. B. Phyllaries.C.Achene and pappus.D. Capitulum. E.Achene. F.Corolla. (drawn by Ms. Ping Liu based on the holotype).