Strobilanthes sunhangii (Acanthaceae), a new species from Tibet, China Author Chen, Jun-Tong Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China & University of Chinese Academy of Sciences, Beijing 100049, China Author Huang, Xian-Han Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China Author Lv, Zhen-Yu School of Life Sciences, Yunnan Normal University, Kunming 650092, Yunnan, China https://orcid.org/0000-0002-0110-005X Author Kuang, Tian-Hui Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China & University of Chinese Academy of Sciences, Beijing 100049, China Author Luo, Jian Institute of Plateau Ecology, Tibet Agricultural and Animal Husbandry University, Nyingchi 860000, Tibet, China Author Deng, Yun-Fei Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, Guangdong, China yfdeng@scbg.ac.cn Author Deng, Tao Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China dengtao@mail.kib.ac.cn text PhytoKeys 2020 166 117 127 http://dx.doi.org/10.3897/phytokeys.166.58831 journal article http://dx.doi.org/10.3897/phytokeys.166.58831 1314-2003-166-117 561609DBFBAA57C79592B7CB04A5CF97 Strobilanthes sunhangii T. Deng, J.T. Chen & Y.F. Deng sp. nov. Figs 1 , 2 , 3 , 4 Type. China. Tibet: Medog County, Beibeng Town, 29.23319N , 95.17693E , elev. ca. 1,470 m, 5 Oct 2018, H. Sun , T. Deng & Z.M. Li Sunhang19964 ( holotype : KUN1345286!; isotypes : IBSC!, KUN1345287!, KUN1345288!) Figure 1. Photograph of the holotype of Strobilanthes sunhangii T. Deng, J.T. Chen & Y.F. Deng (KUN barcode 1345286!). Diagnosis. Strobilanthes sunhangii resembles S. medogensis , but differs by its stems subterete, glabrous (vs. slightly sulcate, bifariously puberulent); spikes (7-)11-22 cm long (vs. 3-6 cm long), rachis glabrous (vs. bifariously pubescent); corolla outside and lobes pinkish-white, inside purplish-pink (vs. corolla yellowish-white, but dull purple on lobes), the tube bent to ca. 90° twice (vs. straight), lobes apices emarginate (vs. rounded); calyx 7-8 mm long, glabrous, 5-lobed to middle (vs. ca. 12 mm long, gland-tipped pubescent, 5-lobed to base), lobes ovate, equal (vs. narrowly oblong-elliptic, subequal); stamens included (vs. exserted), filaments of shorter pair ca. 2 mm long (vs. 7-8 mm long), longer pair ca. 4 mm long (vs. 9-10 mm long), anther thecae ca. 4 mm (vs. ca.1 mm); style with sparse gland-tipped trichomes (vs. glabrous). Figure 2. Strobilanthes sunhangii T. Deng, J.T. Chen & Y.F. Deng A plant showing flowering branch and leaves B flower (view from side) C pistil, ovary and style D calyx E opened corolla showing androecium (Drawn by Xiaoshuang Zhang based on the holotype of Sunhang19964). Description. Undershrubs 1-2 m high, gregarious. Stems subterete, glabrous, slightly swollen at node. Leaves slightly anisophyllous, smaller one ca. 2/3 of the larger one in size; petiole 3-7 mm long or petiole of smaller leaf in each pair shorter, sulcate, glabrous; blades ovate to lanceolate-ovate, smaller ones 4.2-6.9 x 1.2-2.0 cm, larger ones 8.2-10.1 x 2.2-3.2 cm, both surfaces glabrous, densely covered with numerous linear cystoliths, secondary veins 3-5 on each side of midvein and prominent on both surfaces, base rounded to broadly cuneate, slightly oblique, margin serrulate, apex acuminate and narrowly caudate. Inflorescences of axillary spikes, simple or rarely 2-furcate, slender, (7-) 11-22 cm long; rachis glabrous; bracts and bracteoles not seen, caducous. Flowers (0.6-) 1.0-2.5 (-3.0) cm apart on rachis. Calyx 7-8 mm long, glabrous, 5-lobed to middle; lobes ovate, equal, margins narrowly scarious, 1-nerved abaxially, conspicuous after drying, apices acuminate. Corolla 2.8-3.3 cm long, campanulate, outside and lobes pinkish-white, inside purplish-pink, outside glabrous, inside glabrous except for bifarious hirsute retaining the style (Fig. 3E ); tube basally cylindrical, ca. 3 mm wide and ca. 6 mm long, then bent to ca. 90° and gradually widened to 9-12 mm wide at middle and 1.6-1.8 cm long, then secondly bent to ca. 90° and tube upper cylindrical 9-12 mm wide and 1.6-1.8 cm long; lobes broadly elliptic, 8-9 x 7-8 mm, apices emarginate (Fig. 3A, B ). Stamens 4, didynamous, included; the united part of filaments glabrous at base, with dense villous on middle and margin, with slightly sparse villous on upper (Fig. 3E ), shorter pair ca. 2 mm long, longer pair ca. 4 mm long; anther thecae oblong, ca. 4 mm long. Pollen grains prolate in outline, 74.1 (72.2-76.1) x 49.7 (48.1-50.4) μm , P/E = 1.49, tricolporate, ribbed pseudocolpi 12, exine reticulate (Fig. 4 ). Ovary ca. 5 mm long, glabrous; style ca. 1.8 cm long, with sparse gland-tipped trichomes. Capsule not seen. Figure 3. Strobilanthes sunhangii T. Deng, J.T. Chen & Y.F. Deng A habitat and flowering branch B, C flowering branch and flower (view from front) D, E flower (view from side) F calyx G style H leaf adaxial surfaces I leaf abaxial surfaces. Figure 4. Pollen grains of Strobilanthes sunhangii T. Deng, J.T. Chen & Y.F. Deng A equatorial view B polar view C ornamentation. Phenology. Flowering from June-October. Etymology. Strobilanthes sunhangii is named after Prof. Hang Sun (1963-) for his outstanding contributions to the flora of Himalayan regions and collecting this new species for the first time. Verucular name: The Chinese name is given as "双曲马蓝" ( shuang qū mǎ lan ), referring to the double-curved corolla of the new species. Distribution and habitat. The new species is currently known only from Medog County, Tibet, China. It grows in the moist evergreen forest at an elevation of 1,200-1,800 m. The associations include Exbucklandia populnea (R. Br.) R. W. Brown ( Hamamelidaceae ), Viburnum sp. ( Viburnaceae ), Rubus sp. ( Rosaceae ), Campanumoea inflata (Hook. f. & Thomson) C.B. Clarke ( Campanulaceae ), Tripterospermum volubile (D. Don) H. Hara ( Gentianaceae ) and Impatiens sp. ( Balsaminaceae ), amongst others. Conservation status. The new species was only discovered in Beibeng Town, Medog County. About 1,000 individuals were observed and the extent of occurrence was ca. 5 km2. Further explorations to obtain the precise population status are needed to assess its conservation status. Based on available data, the new species is assigned to the category 'Data Deficient' (DD) of the International Union for Conservation of Nature ( IUCN 2019 ). Specimens of S. medogensis examined. - China. Tibet : Medog County, Gedang Town, elev. ca. 2,400 m, 27 Aug1974, QTP Expedition 74-4911 (holotype: KUN barcode 1219209!); Medog County, Gedang Town, 2,450 m elev., 11 Sept 1982, B.S. Li & S.Z.Cheng 814 (PE); Medog County, Gedang Town, 1,940 m elev., 13 Oct 1982, S.Z. Cheng & B.S. Li 1457 (PE); Medog County, 1,100 m elev., 1 Dec 1982, S.Z. Cheng & B.S. Li 3238 (PE); Nyingchi County, Pailong Town, 2,175 m elev., 8 Sept 2006, Tiber-MacArthur 261 (A); Lung County, Chayne chu, 2,750 m elev., 10 Jul 1936, Ludlow & Sherriff 2336 (BM, E). Specimens of S. divaricata examined. - India. Meghalaya : Khasia, 1,524 m elev., 5 Oct 1886, C. B. Clarke 45219 (BM, CAL, LE); Khasia, 1,219 m elev., 12 Nov 1871, C. B. Clarke 15479 (CAL, K, LE); Khasia, Oct 1850, Simons 482 (CAL). Sikkim : Khuping, 1,676 m elev., 26 Sept1884, C. B. Clarke 35904 (LE); Khuping, 1,676 m elev., 26 Sept 1884, C. B. Clarke 35920 (LE). - Nepal. Koshi Zone, Sankhuwasabha District, 2,020 m elev., 16 Aug 1998, S. Noshiroet al. 9840046 (A); Dhawalagiri Zone, Myagdi District, 1,820-2,360 m elev., 10 Sept 1996, M. Mikage et al. 9681329 (A).