Ptilagrostis yadongensis Keng & Tang (1985: 44)

Zhang, Zhong-Shuai, Zhu, Xiang-Yun, Li, Ling-Lu, Jiang, Shan-Wen & Chen, Wen-Li, 2016, A new synonym of Ptilagrostis yadongensis and a new record of Stipa bhutanica to the flora of China (Poaceae), Phytotaxa 272 (1), pp. 94-96 : 95

Ptilagrostis yadongensis Keng & Tang (1985: 44)

Type: — CHINA. Xizang: Yadong , 14 September 1974, Qinghai-Xizang Exped. 74–2496 (lapsus calami as 74–2469; holotype HNWP, isotype PE!). ≡ Ptilagrostis macrospicula Cai (2003: 2018 , excl. Qinghai-Xizang Exped. 74–2674). superfl. name .

= Stipa milleri Noltie (1999: 288) . ≡ Ptilagrostis milleri (Noltie) Nobis & Nobis (2013: 623) . Type:— INDIA. Sikkim: Goichang, Lasha Chhu valley, 4555 m, 19 July 1996, D. G. Long & H. J. Noltie 349 (holotype E, isotype BSHC). syn. nov.

Perennial, forming small dense tussocks. Culms 8–20 cm tall, ca. 0.7–1.2 mm in diam., 2-noded. Leaf blades setaceous, 6–15 cm long; ligules lanceolate, 2–4.5 mm long. Panicles linear, 3–8 × 0.7–1 cm, lowermost branches subtended by two membranous bracts, the bracts ca. 0.8–7 mm long, lanceolate or linear, lower branches paired, 0.3–2.8 cm long, suberect, panicles with 5–12 spikelets. Spikelets dry yellow or purplish; glumes lanceolate, unequal, lower glumes 8.5–13 mm long, upper glumes 7.5–11 mm long, obviously shorter than lower glumes; glumes apex acute, veins inconspicuous; lemmas 5.5–6.7 mm long, glabrous in middle part, gradually pubescent toward base and apex, apical lobes ca. 0.2 mm long, margins completely enclosing paleas; awns 12–19 mm long, 1-geniculate, plumose below bend with 1.3–1.7 mm long hairs, plumose above with 0.3–1 mm long hairs; paleas shorter than lemmas by 0.5–1.5 mm, 2-veined. Caryopses ca. 4 mm long, narrow fusiform, with the widest part in the lower 1/3. Anthers 0.7–1.2 mm long, glabrous at apex.

Morphological notes:— The awns plumose throughout, the lemmas shorter than 8 mm, the anthers ca. 0.7–1.2 mm long are critical characters of Ptilagrostis yadongensis . The emended description was given based on the specimens mentioned above and a population collected by the authors: CHINA. Xizang: Yadong, Pali, 4366 m, 8 October 2015, Z. S. Zhang 600 (PE), 25 individuals.

Ecological notes:— Ptilagrostis yadongensis grows in alpine grassland and we observed members of this species are in fruit during August–October.

Other specimen examined: — CHINA. Xizang: Yadong, Pali, 4366 m, 8 October 2015, Z. S. Zhang 600 (PE). NEPAL. Above Bibre, 4876 m, 29 October 1984, D. J. Miller 215 (K). BHUTAN. Upper Mo Chu district, above Jangothang, 4267 m, 11 October 1987, D. J. Miller 303 (K).