Crotalaria medicaginea Lamarck (1786: 201)

Ninkaew, Sakuntala, Balslev, Henrik, Pornpongrungrueng, Pimwadee & Chantaranothai, Pranom, 2017, Crotalaria L. (Fabaceae: Faboideae) in continental Southeast Asia, Phytotaxa 320 (1), pp. 448-450 : 448-450

24. Crotalaria medicaginea Lamarck (1786: 201) . Type :— INDIA. Sonnerat s.n. (holotype P-LA n.v.) ( Figure 30L ).

= Crotalaria neglecta Wight &Arnott (1834: 192) . Crotalaria medicaginea var. neglecta (Wight & Arn.) Baker (1876: 81) . Type (lectotype designated here):— INDIA. Wight 718 (lectotype E00174392!, isolectotypes E00174390!, E00174391!).

= Crotalaria luxurians Bentham (1843: 578) . Crotalaria medicaginea var. luxurians (Benth.) Baker (1876: 81) . Type (lectotype designated here):— INDIA. 1843, Edgeworth 22 (lectotye K000591082!).

Herb, erect or prostrate, 15–50 cm high; young branches terete, brown pubescent. Leaves digitately 3-foliolate. Stipules narrowly linear, 1–2 mm long, persistent. Petioles 1–1.5 cm long, brown pubescent. Petiolules 0.1–1 mm long. Leaflets obovate or obcordate, 0.3–1.5 × 0.2–1 cm, base cuneate, apex truncate or emarginate, margin entire, glabrous upper, white pubescent lower; lateral veins inconspicuous. Inflorescences terminal or axillary, open racemes, 1–3.5 cm long; peduncle 0.3–1.7 cm long, brown pubescent. Bracts narrowly linear, 0.5–1 mm long, persistent. Pedicels 0.8–2 mm long, brown pubescent. Bracteoles inserted in the middle of the pedicel, narrowly linear, 0.3–0.5 mm long, caducous. Calyx 2.2–2.5 mm long, campanulate, bilabiate; tube 0.8–1 mm long; lobes triangular, 1.4–1.5 mm long, glabrous inside, brown pubescent outside. Corolla yellow. Standard: claw 0.7–0.8 mm long, glabrous; blade elliptic, 2.3–2.5 × 1.7–1.8 mm, base truncate, apex obtuse, margin glabrous. Wings: claw 0.4–0.5 mm long, glabrous; blade oblong, 1.3– 1.5 × 0.7–1 mm, base oblique, apex obtuse, margin glabrous. Keel: claw 0.4–0.5 mm long, glabrous; blade lanceolate, 2.8–3 × 0.8–1 mm, beak spirally twisted, base oblique, apex attenuate, margin glabrous. Stamens: filaments fused for proximal 0.6–0.7 mm, free for distal 1–2.3 mm; anthers either narrowly linear, 0.3–0.5 mm long or oblong, ca. 0.1 mm long. Ovary sessile, elliptic, 1–1.2 mm long, brown pubescent; style 2.8–3.5 mm long with dispersed white pubescence. Pods sessile, broadly ovate, 3–5 × 2–4 mm, brown, brown pubescent. Seeds harp-shaped, 1.5–1.7 × 1.7–2 mm, brown-black.

Representative specimens: — LAOS. Luang Prabang: 18 May 1936, Poilane 26188 ( P) . Vientiane: 14 March 1952, Vidal 1455 ( P) . MYANMAR. Chin State: along the road between Saw and Mindat , 6 December 2012, Fujikawa et al. 90116 ( QBG) . Sagain: 1826, Wallich 5437 ( K) . THAILAND. Buriram: 26 November 1976, Phengklai et al. 3442 ( BKF) . Chiang Mai: Chom Thong , 10 November 1990, Maxwell 90-1251 ( AAU) . Chumphon: Ko Pitak , 1 July 2015, Ninkaew 389 ( KKU) . Kanchanaburi: Chong Sadao , 24 October 2008, Maxwell 08-159 ( QBG) . Khon Kaen: Phu Wiang National Park , 11 November 2014, Ninkaew 281 ( KKU) . Lamphun: Mae Ping National Park , 19 November 1997, Pongamornkul 19 ( QBG) . Loei: Phu Kradueng National Park , 10 November 1970, Charoenphol et al. 4882 ( BKF) . Nakhon Ratchasima: Dan Khun Tod , 17 October 2003, Maxwell 03-339 ( CMUB) . Phetchabun: Nam Nao National Park , 28 October 1984, Murata et al. T-51681 ( BKF) . Prachuap Khiri Khan: Sam Roi Yot , 8 May 1974, Larsen 33735 ( AAU, BKF) . Ratchaburi: 9 August 1966, Larsen et al. 1302 ( AAU, BKF) . Tak: Umphang , 7 November 1998, Puudjaa 512 ( BKF) . VIETNAM. Tonkin : 9 September 1881, Bon 665 ( P) .

Distribution: —North America, Africa, Asia ( India, Sri Lanka, Myanmar, China, Thailand, Laos, Vietnam), Australia. ( Figure 15 ).

Ecology: —Open places and disturbed areas in deciduous dipterocarp, mixed deciduous, evergreen forests and limestone mountains, elevation 50–2000 m.

Notes: — Crotalaria medicaginea is characterized by its obovate or obcordate digitately 3-foliolate leaves and truncate or emarginate leaf apex. Three collections, Edgeworth 22 (K!), Jacquemon s.n. (n.v.) and Hamilton s.n. (n.v.) are mentioned in the original description of C. luxurians . Edgeworth 22 (K!) is designated as the lectotype because it is well preserved. Crotalaria neglecta Wight & Arn. has three duplicates of Wight 718 of which one is chosen as lectotype here.

Figures

FIGURE 15. Distribution map of Crotalaria medicaginea and C. melanocarpa in continental Southeast Asia.

FIGURE 30. Crotalaria in continental Southeast Asia: A & B) C. alata; C) C. albida; D) C. assamica; E) C. bracteata; F) C. chinensis; G) C. goreensis; H & I) C. incana; J & K) C. juncea; L) C. medicaginea; M) C. pallida N) C. sessiliflora and O) C. verrucosa.