Volume 4 > Part 3 > Year 2020 > Page 395 > Leguminosae-Papilionoideae > Derris

4. Derris elegans Graham ex Benth.wfo-0000186135

in Miq., Pl. Jungh. 2: 252. 1852; J. Proc. Linn. Soc., Bot. 4 (Suppl.) 109. 1860; Ridl., Fl. Malay Penins 1: 596. 1922; Merr., Enum. Philipp. Fl. Pl. 2: 299. 1923; Craib, Fl. Siam. 1(3): 488. 1928; Burkill, Dict. 1: 784. 1935; Verdc., Kew Bull. 32(2): 468. 1978; Thoth., Fasc. Fl. India 8: 15, f. 18. 1982; Lock & Heald, Legumes Indo-Chine: 87. 1994; Adema, Blumea 48: 396. 2003; Sirich. et al., Syst. Bot. 37: 414. 2012.

Accepted Name : This is currently accepted.

Synonyms & Citations :

Description : Woody climber; twigs lenticellate, thinly sericeous or strigose. Stipules triangular, 2–5 by 2–5 mm, caducous, outside thinly sericeous to sericeous, inside glabrous. Leaves chartaceous; petiole 1–16 cm long, striate, strigose to glabrous; rachis 1–11 cm long, striate, strigose to glabrous; pulvinus 4–10 mm long, thinly sericeous. Leaflets 3–5; petiolules 5–9 mm long; stipels acicular, 1.5–5 mm long; terminal one elliptic to obovate, 6.5–20.5 by 2.5–9 cm, apex obtuse to rounded or shortly and broadly acuminate, acumen 2–3 mm long, rounded or emarginate, base rounded or subpeltate, rarely cuneate, upper surface glabrous or more or less sericeous on midrib and veins in lower part, lower surface sericeous to velvety, in older leaflets often much less sericeous, then mostly along midrib and veins, midrib and veins raised above, lateral veins 6–10 pairs, 6–29 mm apart, not reaching margin but curving towards apex, sometimes anastomosing near margin, venation reticulate; lateral ones mostly like terminal one, broadly ovate, ovate to elliptic, 4.5–16.5 by 3–7.5 cm; pulvinus of petiolules 2–9 mm long, hirsute to glabrous. Inflorescences axillary and ramiflorous pseudoracemes, sometimes several together forming pseudopanicles, 1.5–23 cm long; peduncle 0.5–20 cm long, thinly hirsute, sometimes strigose; bracts subtending brachyblasts narrowly triangular or narrowly elliptic to ovate, 1–5.5 by 0.3–0.8 mm, outside sericeous, inside glabrous; floral bracts ovate to triangular to elliptic or linear, 0.5–4 by 0.2–0.6 mm, outside sericeous, inside glabrous. Brachyblasts knob-like, shortly cylindrical, up to 2.5 mm long, with 2–3 flowers; pedicels 2.5–9 mm long, hirsute or strigose; bracteoles in upper part of pedicels, often at different heights, narrowly ovate or narrowly triangular to elliptic or linear, 0.5–1.7 by 0.2–0.5 mm, outside sericeous, inside glabrous. Calyx 2.5–4.5 mm high, brownish to purple or red, rarely green, outside sericeous, inside glabrous; tube 2–3.5 mm long; upper lip 0.5–1 by 1.5–4.5 mm, shallowly notched; lateral lobes triangular or semi-circular, 0.5–1 by 1.5–3 mm; lower lobe triangular, 0.5–1.5 by 1.5–2.5 mm. Corolla pale pink to white; standard orbicular, rarely obovate, 8–9.5 by 9.5–10.5 mm, apex emarginate, without basal callosities, outside sericeous or at least with some hairs at the apex, inside glabrous, claw 1.5–3 mm long; wings elliptic, 7–9 by 3–3.5 mm, apex rounded, upper auricle 0.5–1 mm long, lower auricle indistinct, lateral pocket indistinct, outside with some hairs at the ventral side at apex, inside glabrous, claw 2.5–4 mm long; keel more or less boat-shaped, 7–8.5 by 2.5–4 mm, apex rounded, auricle 0.2–1 mm long, lateral pocket 1–2.5 mm long, outside sericeous at upper part, at least at ventral side, inside glabrous, rarely with some hairs at apex, claw 2–4 mm long. Stamens 8–12 mm long, free part of filaments 1–4 mm long, alternately longer and shorter, glabrous; anthers 0.3–0.6 by 0.2–0.4 mm, glabrous. Disc indistinct. Ovary 3.5–6 mm long, sericeous, 2–5-ovuled; stipe 0.5–1 mm long, sericeous; style 4–8 mm long, sericeous at base. Pods more or less oblong to orbicular, 3–6 by 1.5–3 cm, only a single wing along upper suture, sometimes hardly visible, up to 3 mm wide, thinly sericeous. Seeds discoid or bean-shaped, compressed, 9–14 by 7–13 by 1–4 mm; hilum central, 1–2 mm long.

Thailand : SOUTH-EASTERN:Chanthaburi (Makham), Trat (Tha Kum); PENINSULAR: Ranong, Surat Thani (Phunphin), Trang (Thung Wa), Satun (Thung Nui), Songkhla (Khlong Lam Tap, Saba Yoi), Narathiwat (Su-ngai Kolok, Nikhom Waeng).

Distribution : Myanmar (type), Andaman Islands, Laos, Vietnam, Cambodia, Malaysia, Sumatra, Java, Borneo, the Philippines (Mindanao, Palawan), New Guinea, Solomon Islands, Vanuatu.

Ecology : Primary or secondary forests along rivers, to 300 m alt. Flowering: January–March or July–September; fruiting: March–April or July–August.

Vernacular : Ouat nam (อวดน้ำ), ouat lueat (อวดเลือด)(Surat Thani).