Flemingia yunnanensis Franch., 1889

Jiang, Kai-Wen, Tian, Bin & Pan, Bo, 2022, Legume additions to the flora of China, Phytotaxa 532 (1), pp. 1-21 : 7

. Flemingia yunnanensis Franch. (1889–1890: 185). Type:— CHINA: Yunnan, les coteaux de Siao Mi Lang près de Tapintze, 8 th Feb. 1888, J.M. Delavay 3157 (Holotype P00709077!; isotype K!, KUN!, NY!, PE!, SING!, AAU!). Fig. 4.

Description: —Shrub 0.3–1 m, deciduous during the dry season. All parts dense whitish grey tomentose. Branchlets angulate, not lenticellate. Leaves digitately trifoliolate, 5–18 cm; petiole winged, 2–7 cm; terminal leaflet rhomboidovate, 3–11 × 1.5–5.5 cm, while lateral ones smaller and oblique at base; apex of leaflet obtuse, rarely acute. Stipules early caducous, triangular to lanceolate, 3–4 mm. Inflorescence axillary or cauline raceme, 2–7.5 cm. Solitary, or clustered at old branches or rootstock, as many as 10 racemes per node or more. Flower papilionaceous, 11 mm. Bracts tomentose and glandular, triangular to ovate, 3–6 mm, early caducous. Calyx 4 mm, 5-lobed, the lower teeth the longest, outer surface orange glandular and tomentose. Corolla purplish red, all petals subequal in length; standard 8–9 mm, elliptic to ovate, auriculate, short stalked, apex emarginate; wing petals and keel petals long clawed, oblanceolate to obovate. Stamens diadelphous (9+1), 8 mm. Pistil 8 mm, with a shot ovary and long curved style. Pods elliptic, tomentose and glandular, ca. 10 × 5 mm, inflated, 2-seeded.

Distribution and habitat: —This plant occurs in the savanna valleys of Sichuan and Yunnan, which are dry and hot in summer.

Phenology: —Flowering in February to March; fruiting in March to May. Leaves shed at the end of flowering period, and young leaves emerge during the fruiting period.

Taxonomic notes: — Flemingia yunnanensis used to be synonymized with F. wallichii Wight & Arnott (1834a: 242) ( Wei 1991, Wei 1995, Sa & Gilbert 2010). However, F. wallichii bears white flowers, while F. yunnanensis bears purplish red flowers. Do & Gao (2020) synonymized F. yunnanensis with F. macrophylla , which is not dense tomentose all over, flowers in June and September, has larger flowers and leaves, and does not produce cauline flowers. The type specimens (KUN0975083, P00709075, P00709077, P03583162, PE01922573) clearly show the cauline inflorescences, shedding leaves, and the abundant inflorescences from the rootstock. Its cauline inflorescences are unique in the genus. Based on the above evidence, we reinstate Flemingia yunnanensis as a distinct species.

Conservation status: — Flemingia yunnanensis is very narrow distributed and the collection records are rare, so we consider it as a Vulnerable (VU, B a) species according to the IUCN Categories (2019).

Chinese name: —The Chinese name of Flemingia yunnanensis is given here as įff千Ƒffl. “ įff ” means “cauline inflorescences”, while “ 千Ƒffl ” is the common name of the genus Flemingia .

Specimens examined:— CHINA: Sichuan. Dukou, dry and hot valley, alt. 1400 m, 12 th Jun. 1981, W.H. Li & Y. Hu 81-0192 (PE). Dukou, Mar. 1984, G. D. Tao 40139 (HITBC). Yunnan. Heqing, Dapinzi, 27 th Mar. 1888, J. M. Delavay s.n. (NAS00399331). Heqing, Huangping, 9 th Feb. 1990, X. F. Gao 937 (KUN). Yuanjiang, Qingshuihe, riverside, alt. 900 m, 8 th May 1984, G. D. Tao 38045 (HITBC, IBSC).

Discussion: —When he revised the genus distributed in India, Baker (1876) split it into five subgenera, viz. subg. Chalaria ( Wight & Arnott 1834a: 242) Baker (1876: 227) , subg. Flemingiastrum (DC.) Baker , subg. Lepidocoma ( Junghuhn 1845: 338) Baker (1876: 229) , subg. Ostryodium ( Desvaux 1813: 119) Baker (1876: 226) , and subg. Rhynchosioides Baker. This treatment was adopted by later scholars who worked on the taxonomy of the genus Flemingia distributed in India (e. g. Mukerjee 1953, Gavade et al. 2019, 2020). As for Chinese taxa, Wei (1991) also adopted the treatment, while Wei (1995) and Sa & Gilbert (2010) did not adopt it, and neither did Do & Gao (2020), who revised the genus for the Indo-Chinese region.

Molecular work of the genus was conducted by Do et al. (2021), its results showed that Flemingia comprises five clades, in which an African species, Flemingia faginea ( Guillemin & Perrottet, 1831: 212) Baker (1871: 230) formed a single clade, while subg. Rhynchosioides should be merged into subg. Lepidocoma . Careful observation of Flemingia trifoliata showed that this species has tuberous roots as well [ CHINA. Yunnan: Longchuan County, among the roadside bushes, alt. 945 m, 29 th Jan. 1974, G. D. Tao 13414 (HITBC0012891, KUN0753139)]. This morphological evidence supported the above mergence. For other subgenera, F. paniculata Wall. ex Benth. (1852: 245) was originally placed in subg. Chalaria , which should be transferred to subg. Ostryodium based on the phylogenetic results, while F. glutinosa ( Prain, 1897: 438) Y. T. Wei & S. K. Lee (1895: 169) , which was considered as a synonym ( Sa & Gilbert 2010) or a variety ( Do & Gao 2020) of F. lineata ( Linnaeus, 1753: 1054) W. T. Aiton (1812: 350) , should be considered as a distinct species based on the results.

According to the results by previous studies ( Gavade et al. 2019, 2020, Do & Gao 2020), all four subgenera could be found in China. Therefore, we applied the four-subgeneric classification of Flemingia to Chinese taxa and updated the key.