Crotalaria melanocarpa Wallich ex Bentham (1843: 569)

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

25. Crotalaria melanocarpa Wallich ex Bentham (1843: 569) . Type (lectotype designated here):— MYANMAR. On the banks of the Irrawaddy in Pyay (Prome), 1826, Wallich 5382 (lectotype K-W K001120732 , isolectotypes E00814810!, K000591099!, K-W K001120733 ).

Herb, erect, 15–45 cm high; young branches terete, brown pubescent. Leaves simple. Stipules narrowly linear, 1.3– 4.7 mm long, brown pubescent, caducous. Petioles 1.3–4.7 mm long, brown pubescent. Lamina oblong, 0.8–4.2 × 0.3–0.7 cm, base obtuse, apex obtuse, margin entire, both surfaces brown pubescent; lateral veins inconspicuous. Inflorescences terminal, capitate racemes, 1.5–3 cm long; peduncle 5–7 mm long, brown pubescent. Bracts narrowly linear, 1.5–2 mm long, persistent. Pedicels 2–2.5 mm long, brown pubescent. Bracteoles inserted on calyx tube, narrowly linear, 2–2.3 mm long, persistent. Calyx 6–7 mm long, campanulate, bilabiate; tube 1–2 mm long; lobes triangular, 4–5 mm long, glabrous inside, brown pubescent outside. Corolla yellow. Standard: claw 1–1.2 mm long, glabrous, margin white tomentose; blade elliptic, 4–4.5 × 2–3 mm, base obtuse, apex acuminate, brown puberulous, margin glabrous. Wings: claw 1–1.2 mm long, glabrous; blade lanceolate, 4–4.2 × 1.8–2 mm, base oblique, apex acute or obtuse, margin glabrous. Keel: claw 0.8–1 mm long, glabrous, margin white pubescent; blade ovate, 4.5–5 × 2.3–2.5 mm, beak spirally twisted, base cuneate and brown puberulous, apex attenuate, margin glabrous. Stamens: filaments fused for proximal 1.2–1.8 mm, free for distal 1.5–3 mm; anthers either narrowly linear, 0.8–1 mm long or oblong, 0.1–0.2 mm long. Ovary with 1.8–2 mm long stipe, elliptic, 1–1.2 mm long, glabrous; style 8.5–10 mm long, adaxially white puberulous in a single line along the distal edge, abaxially glabrous. Pods with 3–5 mm long stipe, elliptic, 5–6 × 2–3 mm, brown-black, glabrous. Seeds reniform, 0.8–1 × 0.5–1 mm, brown-black.

Representative specimens: — CAMBODIA. Siem Reap: Daugrek, 1928, Poilane 14388 ( P) . MYANMAR. Bago: Pyay (Prome), on the banks of the Irrawaddy, 1826, Wallich 5382 ( K) . THAILAND. Buriram: 26 November 1976, Phengklai et al. 3448 ( BKF) . Chaiyaphum: Nong Bua Daeng , 15 August 1972, Larsen et al. 31883 ( AAU, BKF) . Kanchanaburi: Mueang , 2 November 1979, Shimizu et al. T-21353 ( BK) . Loei: Phu Kradueng National Park , 1994, Vacharee & Santi s.n. ( BK) . Nakhon Ratchasima: Pak Thong Chai , 1 November 1969, Beusekom & Charoenphol 1997 ( AAU, BKF) . Prachuap Khiri Khan: Hua Hin , 11 November 1928, Kerr 16205 ( BK) . Uthai Thani: Huai Kha Khaeng Wildlife Sanctuary , 12 November 1979, Shimizu et al. T-22463 ( BKF) . VIETNAM. Khanh Hoa: Nha Trang , 4 February 1914, Chevalier 30467 ( P) . Ninh Thuan: Phan Rang-Thap Cham, Cana , 28 September 1940, Poilane 30639 ( K, P) .

Distribution: —Asia ( Myanmar, Thailand, Cambodia, Vietnam). ( Figure 15 ).

Ecology: —Open grasslands and open areas in deciduous dipterocarp forests, elevation 20–1100 m.

Notes: —The leaf morphology of C. melanocarpa is quite similar to that of C. montana but it differs in having few branches, capitate inflorescences and stipitate pods. There are four duplicates of Wallich 5382 of which one is designated as lectotype.

Figures

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