Arundinella mainlingensis W. L. Chen & Y. W. Tian, 2025

Tian, Yu-Wei, Zhang, Xie-Yong, Yan, Ping & Chen, Wen-Li, 2025, Arundinella mainlingensis (Poaceae), a new species from Xizang, China, PhytoKeys 257, pp. 65-78 : 65-78

1. Arundinella mainlingensis W. L. Chen & Y. W. Tian sp. nov.

Figs 3 , 4

Type.

China • Xizang, Mainling , roadside cliffs, 29°37′26.75″N, 94°24′13.68″E (DMS), 2922 m elev., 23 Aug 2021, W. L. Chen, X. Y. Zhang 2021-330 (holotype: PE 02534862 !; isotypes: PE 02534861 ! and 02534864!) .

Description.

Perennials, usually densely tufted. Culms 15–35 cm tall, 1–1.5 mm in diam., glabrous, with 3 or 4 nodes. Leaf sheaths with long marginal hairs; ligules truncate, shorter than 0.1 mm; basal blades 3–7 cm long, 1–3 mm wide, firm, densely covered with tubercle-based hairs on the margins and adaxial surface, glabrous on the abaxial surface; basal leaves well-developed, clustered at the base, cauline blades 4–8 (– 10) cm long, 1–3 mm wide, few. Panicles 7–15 cm long, contracted, rachis glabrous or slightly scabrid. Spikelets 4–5 mm long, 2 - flowered, purple, glabrous, in pairs, one long-pedicelled, the pedicel 3 mm long and one short-pedicelled, the pedicel ca. 1 mm long; lower glumes 3–3.5 mm long, ovate-lanceolate, 3 - veined; upper glumes 4–5 mm long, 5 - veined; lower florets ca. 4 mm long, male or neuter; lemmas glabrous, 5 - veined; upper florets ca. 2.5 mm long, bisexual; callus hairy, the hairs ca. 1 / 3 the length of the floret; lemmas of the upper floret slightly scabrid on back, 5 - veined, apex awned, the awns ca. 3.5 mm long, geniculate with brown twisted column; paleas slightly longer than lemma, glabrous; anthers 1.2–1.5 mm long, purplish-red. Caryopses ca. 1.5 mm long, obovate-oblong, brownish.

Distribution and habitat.

The new species is known from Nyingchi, Mainling, Bomê in Xizang, China. It primarily grows on the cliffs along the middle reaches of the Yarlung Tsangpo River, as well as in forest margins and clearings at elevations from 2200–4200 m.

Phenology.

Flowering and Fruiting from July to September.

Etymology.

The specific epithet refers to the type locality, Mainling (Xizang, China).

Specimens examined.

China. Xizang Bomê • alpine meadow in spruce forest, 2700 m elev., 27 Aug 1980, Z. C. Ni, Y. Z. Tian, Tsewang, Thubten 1383 ( PE 00261953 , XZ 0008588 ) • south hillsides, 3150 m elev., 3 Sep 1973, J. Y. Zhang 1434 ( PE 01400609 ) • hillside meadows, 2200 m elev., 19 Jul 1965, J. S. Ying, D. Y. Hong 650642 ( PE 00261949 , 00261947, 00261959) • 3140 m elev., 20 Sep 1973, Qinghai-Xizang Expedition 1460 ( PE 00261950 , KUN 320833 ) ; Mainling • cliffs and forest, 2895–2950 m elev., 26 Oct 2021, W. L. Chen, Y. H. Ma IGDBP 01 -157 ( PE) • 20 Sep 1974, Qinghai-Xizang Expedition Vegetation Group 3295 ( PE 01469368 , KUN 320832 ) • hillsides, 3000 m elev., 12 Sep 1974, Qinghai-Xizang Expedition 74-4650 ( PE 00261945 ) • hillsides, 2970 m elev., 17 Sep 1974, Qinghai-Xizang Expedition 10700 ( PE 01803662 , 01400610) • Under the shrubs, 3030 m elev., 12 Sep 2003, X. F. Gao, W. G. Tu, Y. K. Qiao, H. He 7238 ( CDBI 0197670 , 0197669) • forest, 3050 m elev., 11 Sep 2003, X. F. Gao, W. G. Tu, Y. K. Qiao, H. He 7229 ( CDBI 0197671 , 0197672) • forest, 3030 m elev., 12 Sep 2003, X. F. Gao, W. G. Tu, Y. K. Qiao, H. He 7297 ( CDBI 0197673 ) • riversides, 3930 m elev., 1 Jul 1984, B. C. Wu 84-456 ( FGC 0003249 , 0003250, 0003254) ; Nyingchi • forest, 3050–3070 m elev., 26 Oct 2021, W. L. Chen IGDBJ 01 -17 ( PE) • forest, 3048 m elev., 24 Aug 2021, W. L. Chen, X. Y. Zhang 2021-343 ( PE) • roadside cliffs and forest, 2700 m elev., 12 Sep 1974, Qinghai-Xizang Expedition 74-4648 ( PE 00261952 ) • forest, 2200 m elev., 9 Sep 1980, Ecological Laboratory, Plateau Group 15438 ( PE 01400615 , 01400614, 01400613) • forest, 2250 m elev., 11 Sep 1980, Ecological Laboratory, Plateau Group 15484 ( PE 01400612 ) • forest, 3250 m elev., 16 Sep 1975, Qinghai-Xizang Expedition 7966 ( PE 01400611 ) • meadows, 3100 m elev., Ecological Laboratory, Plateau Group 15691 ( PE 01400608 ) • riversides, 3100 m elev., 16 Sep 1975, Qinghai-Xizang Expedition 7649 ( PE 00261951 , HNWP 50590 ) • wastelands after deforestation, 3200 m elev., 16 Sep 1975, Qinghai-Xizang Expedition 7875 ( PE 01469369 ) • hillsides, 2900 m elev., s. n. 40 ( PE 01432412 ) • hillside meadows, 3040 m elev., 29 Jul 1965, Y. T. Zhang, K. Y. Lang 1118 ( PE 00261958 ) • hillside meadows, 3100 m elev., 31 Jul 1965, Y. T. Zhang, K. Y. Lang 1186 ( PE 00261957 , 00261956) • hillside meadows, 3040 m elev., 28 Jul 1965, Y. T. Zhang, K. Y. Lang 1065 ( PE 00261954 ) • 2100 m elev., 1 Jul 1984, B. C. Wu 84-415 ( FGC 0003251 , 0003252) • hillsides, 2950 m elev., 10 Jul 1984, B. C. Wu 84-475 ( FGC 0003253 , 0003255) • shrubs, 3005 m elev., 13 Aug 2018, J. Hu, D. C. Wang, L. Li, L. Tang sc-a- 084 - B 18 ( CDBI 0262139 ) • shrubs, 3005 m elev., 13 Aug 2018, J. Hu, D. C. Wang, L. Li, L. Tang sc-a- 084 - B 20 ( CDBI 0261963 ) .

Figures

Figure 3. Distribution map of Arundinella mainlingensis and A. yunnanensis. Map source: https://www.tianditu.gov.cn/.

Figure 4. Holotype of Arundinella mainlingensis (W. L. Chen, X. Y. Zhang 2021-330).