Trigonostemon heteranthus Wight

Trigonostemon heteranthus Wight, Icon. Pl. Ind. Orient. [Wight] 5(2): t. 1890 (1852).

Trigonostemon heteranthus Wight; Photo Hoang Thanh Son

Vietnamese name: Tam hùng lá dài, Tam thụ hùng máu

Latin Name: Trigonostemon heteranthus Wight

Synonym Name:

Alchornea cuneata Miq.     

Alchornea cuneifolia (Miq.) Müll.Arg.      

Pseudotrewia cuneifolia Miq.       

Trigonostemon longifolius Baill. ex Müll.Arg.     

Trigonostemon ridleyi Merr. ex Jabl.       

Trigonostemon sanguineus Ridl. 

Wetria cuneifolia (Miq.) Pax

Family: Euphorbiaceae

Description: Small trees, 1–5 m tall, stem up to 7 cm diam; flowering branches 2–5(–7) cm diam. Outer bark 0.1–0.25 mm thick, smooth, pubescent to hispid when young, whitish to brownish; inner bark 0.2–0.4 mm thick, yellowish to reddish brown, soft; sapwood 0.8–1.5 mm thick, white to dark brownish; heartwood 2–3 mm diam. Stipules linear to hook-like, 2–8.5 by 0.3–1 mm, often pubescent. Leaves: petiole terete, 0.4–3.5 cm long, often wrinkled, hispid; blade oblanceolate, (10–)12–28(–46) by (2.8–)4–10(–15) cm, membranous to chartaceous to coriaceous, base cuneate to round, margin distantly serrate, apex acuminate to slightly caudate, upper side glabrous to slightly pubescent, lower side often pubescent to hispid; midrib robust, elevated on both sides, nerves (9–)11–16(–33) pairs, often slightly curved and connected along margin, veins scalariform, veinlets reticulate. Inflorescences uni- or bisexual, axillary or terminal, loose or condensed, per node a single flower or short cymes, rachis (7–)15–30(–55) cm long, 0.5–4 mm diam, pubescent; bracts lanceolate to linear, 3–8 by 0.3–1 mm, pubescent. Staminate flowers 4–5 mm diam; pedicel 1.5 (Thailand, Malay Peninsula, Sumatra)–5 (Borneo) mm long, 0.1–0.2 mm diam, pubescent, base articulate; sepals elliptic, 1.2–2 by 0.7–1 mm, green, margin entire, apex rounded, pubescent outside, glabrous inside; petals spathulate to obovate, 2–2.5 by 1.2–1.7 mm, pinkish to bluish black, base slightly claw-like, sometimes with 2 gland lobes (Thailand, Malay Peninsula, Sumatra), margin entire, apex rounded, smooth outside, often rough and papillose inside; disc annular, 0.2–0.4 mm wide, margin often 5-notched; stamens 3, androphore c. 0.4 mm long, trifid at top, anthers free, divaricate, connective sometimes protruding at top (Thailand, Malay Peninsula, Sumatra). Pistillate flowers 4–5 mm diam; pedicel slightly thickened towards apex, 1.7–3 (Thailand, Malay Peninsula, Sumatra)–9 (Borneo) mm long, apically 0.5–1 mm diam; sepals elliptic to lanceolate, 1.2–1.8 by 0.8–1.5 mm, margin entire, apex rounded to acute, pubescent outside, glabrous inside; petals and disc as staminate flowers; ovary c. 0.7 mm diam, densely pubescent, glabrescent, slightly (Thailand, Malay Peninsula, Sumatra, Borneo, Philippines) to extremely (Borneo) warty; styles short, often indistinct, trifid; stigmas bifid into 2 flattened lobes. Fruits 1.2–1.4 cm diam, green, pubescent, glabrescent, slightly to extremely warty; sepals persistent, not accrescent; wall 0.4–0.6 mm thick, exocarp partly splitting off; columella 5.5–6 mm long. Seeds 6.5–7 by 6–6.5 mm; hilum elliptic to rhombic to heart-shaped, 2–4.5 by 2.5–4 mm.

Distribution: It is found in Thailand, Myanmar (Tenasserim), China, Thailand, Laos, Vietnam, Malay Peninsula (type), Sumatra, Borneo, the Philippines. In VietNam, It is found in Khánh Hòa (Ninh Hòa).

Ecological: Primary evergreen to logged forests, flat land to hill sides, sometimes near rivers, growing on black soil or sandy or stoney clay. Altitude: 15–1600 m.

Flower season: Flowers June-October.

Parts used: Cure Bees stings

Reference:

- theplantlist.org

- efloras.org

- ipni.org

- nationaalherbarium.nl