Alangium solomonense (Bloemb.) W.J.de Wilde & Duyfjes

de Wilde, W. J. J. O. & Duyfjes, B. E. E., 2017, The species of Alangium section Rhytidandra (Alangiaceae), Blumea 62 (1), pp. 75-83 : 81

8. Alangium solomonense (Bloemb.) W.J.de Wilde & Duyfjes , comb. & stat. nov.

Alangium villosum ( Blume) Wangerin subsp. solomonense Bloemb. (1939) 207,f. 6g,7o‒p. ― Lectotype here designated: Brass 3463 (BO; iso A n.v., BISH BISH1000643 , L 2 sheets L.2500050,L.2500051), Solomon Islands, Santa Ysabel Isl. , Sigana, 12 Jan. 1933, fl., fr.

Tree 7–17 m tall; twigs blackish brown, 1.5–3 mm diam, (greyish) brown-hairy in the youngest part, hairs c. 0.1 mm long. Leaves: petiole (0.5‒) 0.8–1 cm long, hairy as the twigs; lamina drying greenish brown, early glabrescent from minute hairs less than 0.1 mm long, (ovate-)elliptic, 6–13 by 2–5 cm, base asymmetric, cuneate, apex acute-acuminate; veins pinnate, 4–6 at each side, tertiary venation thin, reticulate. Inflorescences minutely hairy (hairs ± sparse, less than 0.1 mm long), a single long peduncled compound cyme, 5–15-flowered; peduncle 5–12 mm long. Flowers densely pale brown-hairy, hairs c. 0.1 mm long; pedicel 3–7 mm long; corolla in bud (5‒) 6–8 mm long, base not swollen, apex (sub)obtuse; ovary and calyx (1.5–) 2 mm long, not ribbed; limb narrowly cup-shaped, spreading, c. 0.5 mm long, c. 1 mm wide at margin, lobes 5 (or 6), c. 0.5 mm long; petals 5 or 6, inside glabrous, 7–8 mm long, at base (less than) 1 mm connate; stamens 5 (or 6), filament c. 2.5 mm long, hairy, anther 4–5 mm long, connective glabrous; style 4–6 mm long, hairy, stigma lobes 1–1.5 mm long. Fruit (1–)2–5 per infructescence, ripening yellowish green?, glabrescent, ovoid-ellipsoid, much narrowed towards apex, 17–22 mm long, faintly narrowly ribbed; calyx remnant narrow, small.

Distribution ― Solomon Isl., widespread; in Malesia: Papua New Guinea, Bougainville, where only known from Volk & Robinson NGF 590 (L).

Habitat & Ecology ― Well drained primary rain forest, on flat plain, ridge side and ridge top; brown sandy loam and coral; from sea level to 300 m altitude; flowering and fruiting all year round.

Field-notes ― Common in lowland rain forest; buttresses mostly absent.

Notes ― 1. Alangium solomonense resembles A. pilosum , the latter differs in a slightly smaller corolla, a glabrous style, and smaller fruit.

2. The fruiting pedicel of A. solomonense is 5–10(–20) mm long, longer than generally in the other species of the section.