Crotalaria phyllostachya Gagnepain (1915: 36)

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

33. Crotalaria phyllostachya Gagnepain (1915: 36) . Type (lectotype designated by Phon 1981):— CAMBODIA. Oddar Meanchey:Anlong Veng, 8 November 1927, Poilane 14041 (lectotype P02297500!, isolectotypes K000264009!, P02297501!, P02297502!).

Herb, erect, 50–80 cm high; young branches terete, brown pubescent. Leaves simple. Stipules narrowly linear, 0.5–0.8 mm long, caducous. Petioles 0.5–3 mm long, brown pubescent. Lamina elliptic, oblong or obovate, 0.3–4.5 × 0.2–1.7 cm, base obtuse or cuneate, apex rounded or obtuse, margin entire, glabrous upper, brown pubescent lower; lateral veins inconspicuous. Inflorescences terminal or axillary, somewhat congested, open racemes, 1–4.5 cm long; peduncle 0.3–1.3 cm long, brown pubescent. Bracts narrowly linear, 0.8–2.5 mm long, persistent. Pedicels 0.5–2 mm long, brown pubescent. Bracteoles inserted distally on the pedicel, narrowly linear, 0.5–1 mm long, caducous. Calyx 7–12 mm long, campanulate, bilabiate; tube 2–5 mm long; lobes triangular, 5–7 mm long, glabrous inside, brown pubescent outside. Corolla yellow. Standard: claw 0.8–1 mm long, glabrous; blade obovate, 4.5–5 × 3.2–3.5 mm, base rounded, apex rounded, glabrous above and along the margin, brown pubescent in a single line along the midrib below. Wings: claw 0.7–1 mm long, glabrous; blade oblong, 4.2–4.5 × 2.5–2.8 mm, base oblique, apex obtuse or rounded, margin glabrous. Keel: claw 0.8–1 mm long, glabrous; blade ovate, 5.7–6 × 3–3.2 mm, beak spirally twisted, base obtuse, apex attenuate, margin white puberulous along the distal edge. Stamens: filaments fused for proximal 1–2 mm, free for distal 2–4 mm; anthers either narrowly linear, 0.3–0.5 mm long or oblong, 0.2–0.3 mm long. Ovary sessile, oblong, 2.5–3 mm long, glabrous; style 3.8–4 mm long, adaxially white pubescent in a single line along the distal edge, abaxially glabrous. Pods sessile, oblong, 6–8 × 2–3 mm, brown-red, glabrous. Seeds harp-shaped, 1.2–1.5 × 1.2–2 mm, brown.

Representative specimens: — LAOS. Savannakhet: 13 October 1938, Poilane 28029 ( P) . THAILAND. Nakhon Nayok: Mueang , 6 October 2003, Maxwell 03-311 ( BKF) . VIETNAM. No locality, 22 November 1978, Hiew 504 ( HN) .

Distribution: —Asia ( Laos, Cambodia, Thailand, Vietnam). ( Figure 20 ).

Ecology: —Pine forests, elevation 50–240 m.

Notes: — Crotalaria phyllostachya is a new record for Thailand. Crotalaria phyllostachya is recognized by the combination of its yellow corolla, glabrous leaves, its glabrous standard claw margin and the ovate keel blades.

Figures

FIGURE 20. Distribution map of Crotalaria perpusilla, C. phyllostachya and C. prostrata in continental Southeast Asia.