Flemingia fluminalis C.B.Clarke ex Prain (1897: 438), 1879

Do, Truong Van & Gao, Xin-Fen, 2020, Taxonomic revision of the genus Flemingia (Leguminosae) from Indo-Chinese floristic region, Phytotaxa 429 (1), pp. 1-38 : 20-21

4. Flemingia fluminalis C.B.Clarke ex Prain (1897: 438) . Flemingia strobilifera var. fluminalis (C.B.Clarke ex Prain) Thuan (1979: 143) .

Lectotype (designated by Nguyen 1979):— MYANMAR. Kachin: Hukaung valley , Griffithi 1675 (CAL-0000012300; isolectotype,

P-00709080!)

Flemingia cavaleriei (H. Lév.) Lauener (1970: 244) . Geissaspis cavaleriei H. Lév. (1913: 533) . Lectotype (designated by Do et al.

2018):— CHINA. Guizhou: Pienyang-Lofou route, November 1905, P.J. Cavalerie 2579 (E-00157784!).

Shrublets, erect, ca. 0.5–1 m tall. Branchlets slender grooved, densely pubescent and tomentose on younger parts. Petiole very short, usually 1–5 mm long, hairy. Stipules linear-lanceolate, 0.8–2 cm long, apex with long mucro, persistent or caducous. Leaves 1-foliolate; leaf blade narrowly oblong to lanceolate, 4–8 cm long, 1.5–2.3 cm wide, adaxially adpressedly sparsely pubescent, abaxially densely pubescent, pubescent on both surfaces; basal veins 3, equal, reaching upwards to one-three of the length of the lamina, lateral veins pinnate, 5–8 pairs. Inflorescence a thyrse, terminal or axillary, sometimes branched; inflorescence axis 5–10 cm long, slightly curved, densely pubescent; cymules small, each enclosed by concave bract; bracts subcordate, 0.8–1.5 cm long, 1.5–2.2 cm wide, papery, pubescent on both surfaces, base slightly cordate, apex obviously emarginate. Flowers 1.1–1.3 cm long; pedicel 3–5 mm long, hairy. Calyx tube 3–4 mm long; lobes ovate, equal to or shorter than tube pubescent, covered with scattered small dark brown sessile glands. Corolla cream-yellow, ca. 6 mm long; standard transversely elliptic, auriculate, base shortly mucronate; wings obovate, subequal to standard, one with auricle, long mucronate; keel elliptic, slightly curved, shorter and wider than wings, ca. 4 mm long, apex shortly mucronate. Pods oblong-elliptic, 7–8 mm long, 5–6 mm diam., densely pubescent. Seeds 1 or 2, black, compressed, shining.

Iconography citation: — Pham (1999: 970), figure 3887.

Ecology and phenology: — Flemingia fluminalis grows in mountain slopes and open forest. Flowering starts from January to April; fruiting from March to August.

Distribution: — China, Myanmar, Vietnam, and Laos.

Representative specimens: — VIETNAM. Lai Chau: Phong Tho, Ye Yen Sun , 2 December 1937, M.E.Poilane 26720 (P, AAU) ; 21 January 1938, M.E. Poilane 27164 (P, AAU, IBK). Son La: Van Yen-Van Bu, Petelot 4042 (P). Hoa Binh: Cho Bo, Balansa 2191 (P) . LAOS. Louang Prabang: Spire 874 (P, VNM-00012558) ; Muong You-Dan Quan , elev. 400–500 m, 14 February 1932, M.E.Poilane 20132 (P) ; August 1866, Thoul s.n. (VNM-00012562). Khammouane, Ban Poung Luang , December 1930, Petelot s.n. (P) . CHINA. Yunnan: 24 March 1961, Y.H. Li 3011 (HITBC-019240) ; Xishuangbanna, Jinghong, Nabanhe , 12 November 1988, G.D.Tao 44875 (HITBC-019237) ; Puer, Xiaoheijiang River , 3 March 1990, G.D.Tao 41525 (HITBC-019239) ; 14 November 2005, S.S.Zhou 3244 (HITBC-0012862); Mengla, Songbingshan , elev. 500 m, 3 January 2011, J.W.Li 233 (HITBC-0012861) ; Shizhong, near Wulong Naji, elev. 900 m, 18 November 1984, H.Sun et al. 0317 (KUN). Guangxi: Tianlin , Hongshui River , elev. 200 m, 20 November 1957, Z.Q.Zhang 10905 (KUN-0814924, IBK-00072312) ; Baiyang, Hongshui River , elev. 150 m, 27 March 1960, Z.S.Zhang & Y.T.Zhang 7 (IBSC-0179639). GuiZhou: Luodian, Fending, 12 April 1959, Quiannam team 00474 (PE-00379633). Sichuan: Jingyang, Diaoping, elev. 560 m, 2 August 1976, Sichuan Exp. Team 14818 (CDBI-0058747) . THAILAND. Mae Hong Son, Muang, Bang Mu, elev. 250 m, 20 February 1979, T.Koyama et al. 15455 (AAU). Doi Chieng Dao : December 1979, A.Ubolchalaket s.n. (AAU) .

Perennial herbs, erect, ca. 1 m tall. Branchlets densely bulbous-based hairs and glands. Petiole 2–3 cm long, triquetrous, densely hair; petiolules 2–3 mm long, densely hirsute. Stipules broadly ovate, 7–10 mm long, 2.5–4 mm wide, striate, apex acute, densely hairy, caducous. Leaves digitately 3-foliolate and 1-foliolate; leaflets obovate to broadly obovate or ovate, rarely elliptic, frequently lanceolate in upper leaves, terminal leaflet slightly larger than lateral one, (–1)5– 6(–7) cm long, (0.5–) 3–5 cm, both surfaces densely bulbous-based hairs and reddish glands, apex acute, base cuneate or oblique, margin hairy; basal veins 3, lateral veins 3–5 pairs. Inflorescence simple or compound capitate with few branches, axillary or terminal, densely hairy, enclosed by involucres of bracts when young, up to 6 cm long, consisting of 4–7 flowers per head; inflorescence axes up to 6 cm long; bracts broadly ovate, involucrate, imbricate 7–9 mm long, 4–5 mm wide, apex acuminate, densely hair; pedicel ca. 2 mm long, densely hairy; bracteoles absent. Calyx tube 3.5–4 mm long, upper 2-lobed, 9 mm long, 2.5 mm wide; lower 3-lobed, middle one broadest and longest, ca. 10 mm long, densely hairs. Corolla much longer than the calyx, dark purple to pinkish; standard broadly obovate, ca. 16–17 mm long, 13–14 mm wide; claw 4.2–5.2 mm long, auriculate; wings obovate, ca. 9–10 mm long, 5–6 mm wide; claw 5.5–6 mm long, auriculate, apex acute, margin entire, dark-purple; keel falcate, 8 mm long, 4.5–5 mm wide. Ovary glandular, sparsely hairy, 2.5–3 mm long; style filiform, 12–13 mm long; stigma capitate. Pods turgid, 6–7 mm long, 4–5 mm diam., densely hairy and glandular. Seeds 1 or 2, black, subglobose, ca. 2.5 mm diam.

Iconography citation: — Mattapha et al. (2017: 11), figures 1–2.

Ecology and phenology: — Flemingia sirindhorniae grows on dipterocarp forest on degraded limestone rocks and sandy soil, sometimes growing on steep limestone cliffs. Flowering starts from August to October, and fruiting from November to December.

Distribution: —Endemic to Thailand.

Notes: — Flemingia sirindhorniae is most similar to F. trifoliata in having capitate inflorescences enclosed by involucres of bracts; however, it differs from the latter in having leaves 1-foliolate and 3-foliolate, fewer flowers in the heads and the flowers are larger, the length of corolla is much exceeding the calyx tube.

Representative specimens: — THAILAND. Tak: Umphang, Umphang Wildlife Sanctuary, D.J.Middleton et al. 5751 (AAU, SING).