Agapetes putaoensis, a Newly Recorded Species of Agapetes (Ericaceae) from China

YANG Bin, LI Jianwu, LI Haitao, ZHOU Lumen, TAN Yunhong*

(1 Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw 05282, Myanmar; 2 Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; 3 Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, Yunnan 666303, China; 4 Yunnan Branch, Institute of Medicinal Plant, Chinese Academy of Medical Sciences/Yunnan Key Laboratory of Southern Medicinal Resources, Jinghong, Yunnan 666100, China; 5 Management and Conservation Bureau of Yunnan Huangliangshan National Nature Reserve, Lüchun, Yunnan 662599, China)

Abstract: Agapetes putaoensis Y. H. Tong & N. H. Xia was originally described from Putao District, Kachin State, northeast Myanmar in 2014. The present authors collected it from Lüchun County, Yunnan, China in 2018 and 2020. Here, it is reported as a newly recorded species for China. This species is described and illustrated with a colour plate for identification. Supplementary description of its fruits is also provided. The voucher specimens are deposited in the Herbarium of Xishuangbanna Tropical Botanical Garden (HITBC) and the Yunnan Branch, Institute of Medicinal Plant, Chinese Academy of Medical Sciences (IMDY).

Key words: Agapetes; Ericaceae; Agapetes putaoensis; new record; Myanmar

The genusAgapetesD. Don ex G. Don (Ericaceae: Vaccinioideae: Vaccinieae), comprises approximate 100 recognized species, most of which are distributed from the eastern Himalayas through Southwest China and Indochina to Southeast Asia[1]. In China, 55 species and 2 varieties are currently recognized, including the recently publishedA.xianaY. H. Tong andA.yingjiangensisY. H. Tong, B. M. Wang & N. H. Xia[1-4].

During the traditional Chinese Medicine resource and floristic surveys of southeastern Yunnan, China in 2018 and 2020, we collected some specimens of anAgapetesspecies. After a detailed examination of the morphological characters of our material and related literatures, we identified it asAgapetesputaoensisY. H. Tong & N. H. Xia which was recently described by Tong and Xia[5]from Kachin state, Northern Myanmar. It therefore represents a newly recorded species for the flora of China, which was reported herein.

葡萄樹蘿卜(新擬，圖版Ⅰ)

AgapetesputaoensisY.H.Tong&N.H.Xia,Phytotaxa184(1):39,2014.(Plate Ⅰ)

Type: Myanmar. Kachin State: Putao, Renan, epiphytic on trees, 27°42′6″N, 98°2′14″E, elevation 970 m, 15 March 2009, Ayeyarwady Expedition 2416 (holotype: IBSC; isotypes: CDBI, IBSC).

Shrubs epiphytic, ca. 2.5 m tall. Twigs longitudinal-striate, glabrous. Leaves spirally scattered; petiole 4-6 mm long, glabrous; blades elliptic-lanceolate, 5-11.3 × 1.1-2.9 cm, thinly leathery, glabrous, midveins raised on both surfaces, secondary veins 3-5 pairs, with fine veins slightly conspicuous on both surfaces, base attenuate to cuneate, margin entire, slightly revolute, apex caudate-acuminate. Inflorescences axillary or on leafless stem, 1-5-flowered; peduncle very short, 1-2 mm long; bracts triangular, ca. 0.5 mm long, glabrous; pedicels 1.2-2.0 cm long, glabrous, expanded upwards. Calyx tube white, tubular, 2.5-3.0 × ca. 2 mm, glabrous; lobes triangular, ca. 1 mm long, glabrous, apex acute. Corolla reddish white, cylindric-conical, 0.8-1.0 × 0.2-0.3 cm, glabrous; lobes triangular-lanceolate, 5-6 mm long, strongly reflexed at late flowering. Stamens 10, 0.9-1.0 cm long; filaments flat, ca. 1 mm long, margin white pubescent; thecae 1.5-2.0 mm long, papillate; tubules 6.0-6.5 mm long, with 2 spurs abaxially, spurs ca. 1 mm long. Style glabrous, ca. 1 cm long. Fruit subglobose, greyish-white when mature, 4-5 mm in diameter.

Distribution: China (Yunnan) (new record); Myanmar (Kachin).

Specimensexamined: China(中國). Yunnan(云南): Lüchun County(綠春縣), Qimaba Village(騎馬壩鄉(xiāng)), Huangliangshan National Nature Reserve(黃連山國家級自然保護區(qū)), 22°50′30.75″N, 102°14′41.15″E, 1 100 m, 11 April 2020, Li Jianwu(李劍武) 5402 (HITBC); Sanmeng(三猛鄉(xiāng)), Lagu(臘姑村), 1 500 m, 10 April 2018, Lüchun Team(綠春考察隊)5326310565 (IMDY).

Discussion: The comparative analysis of the floristic similarities showed that the flora of Dulongjiang has closer affinity with the flora of SE Yunnan than others although it is distant away from SE Yunnan[6-7]. One of the possible ways to explain the closer floristic affinity between Dulongjiang and southeastern Yunnan is from the geology and the tectonic theory of these regions. Meanwhile, the geological history of SE Asia revealed that the west and South Yunnan could be derived from fragments of Gondwana[8]. During the proceeding of the northward thrusting of Indian plate to Asian continental plate and the uplift of the Himalayas and the Hengduan Mountains, the Gondwana fragment of Yunnan had turned clockwise. Dulongjiang area and Northeast Myanmar belong to the same geographic area, therefore it could be possible that this species occurs in the disjunctive areas of Northeast Myanmar and SE Yunnan.

Additionalspecimensexamined: Myanmar(緬甸). Kachin State(克欽邦): Putao township(葡萄鎮(zhèn)), Wasadam, 29 April 2016, Tan Y. H.(譚運洪)& Zhou S. S.(周仕順), M201634 (HITBC); Putao(葡萄), on the way from the mountain top to Namti, 14 May 2017, Tan Y. H.etal.(譚運洪等), M1777(HITBC), Putao(葡萄), Northwest of Zeyadam, on the way from Camp 1 to Zeyadam, 12 May 2017, Zhou S. S.(周仕順)& Zeng X. D.(曾曉東), M2123 (HITBC).

AcknowledgmentsWe are very grateful to the reviewers for their valuable comments and suggestions. The first author thanks Dr. Song Yu and Mr. Li Kunju for their help in the field.

圖版Ⅰ葡萄樹蘿卜 A和D.果枝；B和E.花；C和F.花解剖；A-C拍自云南省綠春縣；D-F拍自緬甸克欽邦葡萄；A由李劍武拍攝；B由李海濤拍攝；C由楊斌拍攝；D-F由譚運洪拍攝
PlateⅠAgapetesputaoensisY. H. Tong & N. H. Xia A & D. Fruiting branches; B & E. Flowers; C & F. Dissected flowers; Photos A-C taken from Lüchun, Yunnan, China; D-F taken from Putao, Kachin, Myanmar; A by LI Jianwu; B by LI Haitao; C by YANG Bin; D-F by TAN Yunhong.