Alphonsea yunnanensis (P. T. Li) Y. H. Tan & Bin Yang, 2025

Yang, Bin, Zuo, Yun-Juan, Wang, You-Bing, Yang, Chang-Ji, Guo, Yong-Jie, Ding, Hong-Bo & Tan, Yun-Hong, 2025, Taxonomic status of Orophea yunnanensis (Annonaceae), an endemic plant species in Yunnan, China, PhytoKeys 267, pp. 43-58 : 43-58

Alphonsea yunnanensis (P. T. Li) Y. H. Tan & Bin Yang comb. nov.

Fig. 3

Orophea yunnanensis P. T. Li , Acta Phytotax. Sin. 14 (1): 106. 1976. Type: CHINA. Yunnan Province: Jiangchuan County, Luchong, Bijiashan , 1 April 1940, F. C. How 74518 ( holotype: IBSC [0003364], isotype: IBSC [0003363]) .

Alphonsea yunnanensis Bân , Siméon Tén 345 (L [0192066]), nom. nud.

Alphonsea yunnanensis (P. T. Li) X. L. Hou (2003: 172), nom. inval. (Art. 30.1).

Description.

Small trees, 3–10 m tall, ca. 5–25 cm dbh. Bark grayish black, fissured. Young twigs brownish or grayish black, puberulent to glabrous. Petioles 2–4 mm long, 0.9–1.5 mm in diameter; leaf blades oblong-elliptic to oblong-ovate, 4.2–14.3 × 1.5–4.0 cm, base cuneate to obtuse, apex acute to attenuate, leathery, adaxially sparsely puberulent to glabrous, abaxially glabrous; midrib slightly impressed and sparsely puberulent to glabrous above, raised and sparsely puberulent below; secondary veins 10–20 on each side of the leaf, anastomosing within margin, prominent above, distinctly raised below; tertiary veins reticulate, prominent abaxially and adaxially. Inflorescence leaf-opposed or supra-axillary; 1–4 flowers per inflorescence. Peduncles absent or up to 2.5 mm long. Pedicels (2.0 –) 5.5–8 mm long, 0.8–1.0 mm in diameter, puberulous, with one pubescent median or basal bract. Flowers yellow, 1.0– 1.4 cm in diameter when fresh. Sepals ovate, 0.7–1.0 (– 1.5) × 1.4–1.7 (– 2.0) mm, pubescent abaxially, sparsely puberulent to glabrous adaxially; outer petals ovate, 9–12 × 6–8 mm when fresh, 7–9 × 5–6 mm when dry, base cuneate to attenuate, apex acute, pubescent abaxially, puberulent adaxially; inner petals narrower, 11–14 × 5–7 mm when fresh, 10–12 × 4.5–5.5 mm when dry, base cuneate, apex acute, puberulous to puberulent abaxially, sparsely puberulent to glabrous adaxially. Stamens “ miliusoid ” with very short connective prolongation not extending over pollen sacs, 20–30 per flower, ca. 1 mm long, in 3 whorls. Carpels 2–6 per flower, ca. 1.5–2 mm long, puberulous to puberulent; ovules ca. 8 per carpel, biseriate. Fruiting pedicels 6.5–7.8 mm long, 1.7–2.6 mm in diameter; monocarps 1–4 per fruit, subglobose to oblate, 2.1–3.4 cm long, 2.0– 2.7 cm in diameter, yellow when mature, shortly pubescent, smooth, apex rounded; stipes 3.5–4.6 mm long, 2–2.6 mm in diameter. Seeds up to 8 per monocarp, flattened ellipsoid, 1.6–2.1 cm long, 0.9–1.3 cm wide, 0.5–0.8 cm thick; endosperm rumination lamelliform.

Phenology.

Flowering from January to May, and fruiting from July to September.

Distribution and habitat.

According to our field investigation and herbarium records, Alphonsea yunnanensis is distributed in several localities of 16 counties and cities across the Yunnan Province (Fig. 4 ; Chen et al. 2024). It has small trees growing in subtropical limestone evergreen-deciduous broad-leaved mixed forests at 1000–1800 m elevations. As field surveys progress, additional populations are expected to be discovered in its distribution ranges.

Conservation status.

This species was previously assessed as critically endangered ( CR) ( IUCN 2004; Li and Gilbert 2011) and listed as a Plant Species with Extremely Small Populations ( PSESP) in Yunnan ( Ren et al. 2016; Sun 2021). According to the current distribution of Alphonsea yunnanensis (Fig. 4 ), the extent of occurrence ( EOO) for it is 95,142 km 2 and the area of occupancy ( AOO) is 76 km 2, as calculated by Shiny-GeoCAT ( Moat et al. 2023). Based on our initial field investigation, the average number of flowering and fruiting individuals in the wild populations is less than 5. Most distribution points are located on limestone hills or at the edges of river valleys, and they are vulnerable to disturbances. Based on the IUCN Red List Categories and Criteria ( IUCN 2024), notably on the number of locations, mature individuals and the AOO, this species qualifies for classification as Endangered ( EN, B 2 ab (iii, v) D).

Additional specimens of Alphonsea yunnanensis examined.

China. Yunnan Province: • Binchuan City, Kee y la, via Pe yen tsin ad Pin tchoan ( Geyila , 25°55'40.8989"N, 100°56'48.4531"E, 1790 m), 18 April 1917, S iméon Tén 345 ( US [03804827], A [00056744], L [0192066], P [01956285]) ; • Pay Keau tsui , 13 April 1906, F. Ducloux 4681 ( P [01956282, 01956284]) ; • 8 February 1909, F. Ducloux 6752 ( L [0192065], P [01956281]) ; • Changning County, ca. 5 km from Xiyi Township to Kejie Town , 7 April 2022, 24°54'13.26"N, 99°23'13.55"E, 1678 m, Yong-Jie Guo, Xiao-Qiang Tao, Xing-Xu Sun 22 CS 22416 ( KUN) ; • Chengjiang City, Luchong Village , 24°33'27.50"N, 102°50'21.45"E, 1727 m, 12 March 2014, Jie Cai, Ting Zhang and Chang-Hong Li 14 CS 9025 ( KUN) ; • Luchong scenic spot, Bijiashan , 24°33'56.77"N, 102°50'40.24"E, 1715 m, 18 April 2020, Bin Yang T 0493 ( HITBC) ; • ibid, 3 May 2020, Li-E Yang and De-Li Peng T 0495 ( HITBC) ; • ibid, 4 August 2021, De-Li Peng YB 1045 ( HITBC, PE) ; • ibid, 24°33'57.58"N, 102°50'39.77"E, 1690 m, 30 August 2023, Bin Yang and Jian-Guo Chen YB 1400 ( HITBC) ; • Daoyao County, Sanchahe Town, Rentouguan Village , 25°47'48.30"N, 100°57'25.08"E, 1458 m, 17 August 2024, You-Bing Wang, Jian-Jun Yang, Hao-Feng Dong YB 1793 ( HITBC) ; • Fugong County, Pihe Township , 26°32'0.07"N, 98°53'45.52"E, 1079 m, 13 March 2024, Xiao-Qiang Tao YB 1573 ( HITBC) ; • Huaning County, Panxi Town, Xiaolongtan , 1000 m, 10 August 2016, En-De Liu, Li-Chun Ma and Yun-Hua Xia 4811 ( KUN) ; • ibid, 24°11'4.65"N, 103°5'51.72"E, 1097 m, 12 January 2024, Bin Yang and Shi-Bo Yuan YB 1491 ( HITBC) ; • Jianshui County, on the way from Yangjieba to Gantang , 17 March 1941, Tchen Ngo Liou 18347 ( PE [01161779, 01161777], IBSC [0077084]) ; • Xizhuang Town, Huanglong zen temple , 23°38'55.85"N, 102°45'40.26"E, 1302 m, 30 April 2022, Bin Yang and Yun-Hong Tan YB 1155 ( HITBC) , ibid, 11 January 2024, Bin Yang, Shi-Bo Yuan YB 1489 ( HITBC) ; • Lanping County, on the way from Tu’e Township to Zhongpai Township , 1419 m, 11 March 2009, Shi-Shun Zhou 5254 ( HITBC) ; • Longyang District, along the west side of the Lancang Jiang (Mekong River) upstream from Yangbao Bridge on route G 320, site of government-closed gold mining operation , 25°28'40"N, 99°20'10"E, 1300 m, 6 August 2019, David E. Boufford, Jian-Ling Guo, Lin Su 45549 ( P [01105919, 01106103]) ; • Lujiang Town, Danggang Village , 25°8'11.39"N, 98°48'46.97"E, 1201 m, 27 May 2022, Ping-Yuan Wang, Bin Yang, Xiao-Dong Zeng et al. T 2435 ( HITBC) ; • ibid, 25°5'53.57"N, 98°47'54.44"E, 1119 m, 28 May 2022, Ping-Yuan Wang, Bin Yang, Chang-Ji Yang et al. T 2444 ( HITBC) ; • ibid, Zhanggong Village, Kunmeng river , 25°5'50.48"N, 98°48'0.40"E, 1029 m, 5 April 2023, Bin Yang, Yong-Jing-Wen Yang, Jia-Qiang Dong YB 1287 ( HITBC) ; • Mile City, Xinshao Town , 2 September 2010, Chong-Jiang Zhao 146 ( HITBC [0040077]) ; • Dongshan Town , 24°10'48.88"N, 103°32'21.19"E, 1357 m, 12 January 2024, Bin Yang, Shi-Bo Yuan YB 1492 ( HITBC) ; • Nanjian County, Shale Township, Shale Village, Yindian river , 24°45'30.94"N, 100°25'33.33"E, 1273 m, 1 July 2015, En-De Liu, Wei Fang, Zhou-Feng Xu et al. 4402 ( KUN) ; • ibid, 20 March 2020, Hai-Lei Zhen T 0459 ( HITBC) ; • Ning’er County, Ning’er Town, Longdong Village , 1500 m, 8 January 2018, Shi-Shun Zhou 14832 ( HITBC) ; • ibid, 23°5'3.24"N, 101°1'8.87"E, 1432 m, 3 October 2023, Bin Yang YB 1441 ( HITBC) ; • Xiangyun County, Midian Town, Chalangshao Village , 25°46'56.22"N, 100°55'58.96"E, 1474 m, 17 August 2024, You-Bing Wang, Jian-Jun Yang, Hao-Feng Dong YB 1792 ( HITBC) ; • Xinping County, Yubaiding state forest farm, Yanihe , 24°5'2.82"N, 102°7'39.71"E, 1306 m, 29 March 2020, Kai-Chun Xiong T 0466 ( HITBC) ; • Yangbi County, Huimin bridge to Dacun village , 9 November 1946, Tchen Ngo Liou 22706 ( PE [01161778], IBSC [0077088]) ; • Yuanjiang County, exact location unknown, s. d. (presented by Dr. A. Henry, 1901), A. Henry 13333 ( K [003305217], NY [04348761, 04725671]) .

Figures

Figure 3. Morphological characters of * Alphonsea yunnanensis. A. Habit; B. Flowering branch (back view); C. Fruiting branch; D. Flower buds; E. Unopened flowers (side view); F. Opened flowers (back view); G. Opened flowers (front view); H. Dissection of a flower (H 1 sepals H 2 outer petals H 3 inner petals H 4 stamen H 5 carpel); I. Fruit; J. Seeds (J 1 immature seeds J 2 mature seeds J 3 longitudinal dissection of a seed).

Figure 4. Distribution of * Alphonsea yunnanensis.