Saussurea ramchaudharyi S.K. Ghimire & H.K. Rana, 2018

Rana, Hum Kala, Sun, Hang, Paudel, Asha & Ghimire, Suresh Kumar, 2018, Saussurea ramchaudharyi (Asteraceae), a new species from Nepal, Phytotaxa 340 (3), pp. 271-276 : 272-274

Saussurea ramchaudharyi S.K. Ghimire & H.K. Rana , sp. nov. ( Figs. 1–3 )

Type:— NEPAL. Humla , upper Chungsa valley, above Seliman Lake, rocky and scree slope, 30°08.623’N, 81°42.94’E, 4650 m a.s.l., 10 September 2012, S.K. Ghimire, A. Poudel, C. Thapa, L.R. Joshi, S. Lo, & P. Subedi CHH-1247 (holotype: TUCH; isotype: KATH) .

Diagnosis:—Monocarpic herb, 4–6 cm tall; caudex unbranched; stem axis short 2.5–3 cm; leaves almost prostrate on ground, upper leaves greenish purple, extending half of length of capitula; synflorescence 3.5–4.5 cm in diameter, exposed and surrounded by uppermost stem leaves; involucre broadly campanulate; phyllaries 4-seriate, inner phyllaries apically glabrous; achene much smaller ≤ 2 mm with glabrous apex and inner bristles of pappus shorter than corolla.

Description:—Perennial monocarpic herb, 4–6 cm tall. Caudex unbranched, covered with leaf remains. Stem erect, simple, club-shaped, hollow, shorter 2.5–3 cm long with 1.5–2.2 cm broad apex. Leaves in rosette, almost prostrate on the ground, linear to narrowly oblanceolate; green or purplish green; midvein distinct, apex acute; margin sparsely denticulate to pinnatilobed in upper half; lobes 6–10 pairs, somewhat curving upward from half of length. Basal or lower leaves petiolate, narrowly oblanceolate, 8.5–10.2 × 0.5–0.9 cm, thinly pilose or glabrous; lobes 1.5–3 mm; petiole reddish purple. Upper leaves sessile, linear to narrowly oblanceolate, 5–9.5 × 0.3–0.8 cm; lower part pilose (covered with woolly hairs); lobes 1–2 mm. Synflorescence 3.5–4.5 cm across, aggregated in the center of leaf rosette, terminal on stem, exposed and surrounded by densely pilose subtending uppermost stem leaves. Capitula more than 15, sessile, crowded at the apex. Involucre campanulate, 1.2–1.5 cm in diameter. Involucral phyllaries 4–seriate, imbricate, 0.8–1.8 × 0.15–0.25 cm, membranous; outer linear to lanceolate, densely pilose; inner linear or narrowly lanceolate, glabrous, apex acute. Receptacle convex, setaceous; bristles 1.5–2 mm. Corolla fused at most of its length, glabrous, dark purple, 9–11 mm; tube 4–5 mm; limb 5–7 mm including ca. 1–1.5 mm long lobes. Stamen 1–1.2 cm, head ± tapered, tail glabrous. Carpel-1, style slender, 1-1.2 cm long, stigma bilobed. Achene ≤ 2 mm, with curved base, glabrous apically. Pappus 2-seriate, whitish or straw-colored; outer series caducous, with scabrid bristles, 3–4 mm long; inner series persistent, plumose, 7–8 mm long, bristles shorter than corolla.

Phenology:—Flowering and fruiting from August to October.

Distribution and habitat:— Saussurea ramchaudharyi is currently known only from the type locality in upper Chungsa Valley, Humla district, Nepal at elevation 4640 m a.s.l. ( Fig. 1A, 1B, 1C, 1D ). It grows on alpine rocky and scree habitat with exposed slope ( Fig. 1C, 1D ; Fig. 2A, 2B ).

Etymology:—The specific epithet is given in honor of Dr. Ram Prasad Chaudhary, a renowned Nepali plant taxonomist and professor of botany, who has made great contributions to the conservation of biodiversity in the Nepal Himalaya.

Conservation status:— Saussurea ramchaudharyi is a very locally endemic species, restricted to a single mountain ( Fig. 1B, 1D ). We recorded less than 30 mature individuals of S. ramchaudharyi in the type locality within an area of ca. 500 m 2. The main threat to the habitat and the species is related to high anthropogenic pressure, such as livestock grazing, and harvesting of caterpillar fungus and other medicinal and aromatic plants. Owing to its highly restricted distribution in a fragile and isolated alpine habitat, its small population size as well as the observed and projected decline in habitat quality due to anthropogenic pressure, S. ramchaudharyi is categorized as Critically Endangered [CR; B1ab (iii), B2ab (iii) and D] based on the IUCN Red List categories and criteria version 3.1 ( IUCN 2012).

Figures

FIGURE 1. Distribution of Saussurea ramchaudharyi. (A, B) Distribution map showing type locality in Nepal (A) and Humla district (B). (C, D) Type locality habitat at Upper Chungsa valley, Humla district (C–D by S.K. Ghimire).

FIGURE 2. Saussurea ramchaudharyi. (A, B) Reproductive plant. (C) Vegetative plant (A–C by S.K. Ghimire). (D) Synflorescence exposed at anthesis (by H.K. Rana).

FIGURE 3. Saussurea ramchaudharyi (based on the holotype). (A) Habit. (B) Leaf (B1: upper leaf, and B2: lower leaf). (C) Floret with pappus. (D) Phyllaries (outer to inner from right→left). (E) Stamens. (F) Achene with pappus (drawn by H.K. Rana).