Alangium glabrum W.J.de Wilde & Duyfjes, 2017

de Wilde, W. J. J. O. & Duyfjes, B. E. E., 2017, The species of Alangium section Rhytidandra (Alangiaceae), Blumea 62 (1), pp. 75-83 : 78

3. Alangium glabrum W.J.de Wilde & Duyfjes , sp. nov.

Resembling Alangium strigosum W.J.de Wilde & Duyfjes but differing in whole plant glabrescent from minute hairs 0.1 mm long, lamina 8–11 cm long,and fruit c. 30 mm long (twigs densely rusty or golden brown-hairy,hairs 0.5‒1 mm long,lamina 13–19 cm long, and fruit 12–15 mm long in A. strigosum ). ― Type: Womersley & Woolliams NGF 37092 (holo L L2500143 ;iso A, BO, BRI, CANB, K, LAE, SING, SYD,all n.v.), Papua New Guinea, Southern Highlands Province, Sawmill at Ialibu , 2000 m alt., 14 Sept. 1967, fl., fr .

Etymology. The specific epithet ‘ glabrum ’ refers to the overall glabrous aspect of the plant.

Tree c. 12 m tall; twigs brown, 1–2.5 mm diam, whole plant glabrescent from minute greyish brown hairs c. 0.1 mm long. Leaves: petiole 0.6–0.8 cm long; lamina drying brownish green, elliptic, 8–11 by 3.5–5 cm, base (slightly) asymmetric, rounded or broadly short-cuneate, apex long acute-acuminate; veins (3 or) 4 or 5 at each side, tertiary venation reticulate. Inflorescences minutely hairy as the twigs, glabrescent, simple, 2- or 3-flowered, peduncle (5–) 10 mm long. Flowers densely minutely brown-hairy, hairs c. 0.1 mm long; pedicel c. 2 mm long; corolla in bud (only seen in immature flowers) presumably 8–10 mm long, 1(–1.5) mm diam, base not swollen, apex narrowly obtuse; ovary and calyx c. 3.5 mm long, coarsely 4–8-ribbed, minutely greyish brown-hairy; limb c. 1.5 mm long, including 4 triangular lobes 0.7–1 mm long, somewhat spreading; petals 4, inside thinly hairy towards base; stamens 4, mature filaments and anther not known; immature filament sparingly hairy, connective glabrous; style glabrous. Fruit 1–3 per infructescence, ripening green (?), glabrescent (except at very apex), narrowly ellipsoid, broadest slightly below the middle and pointed (narrowed) at both ends, (25‒) 30 mm long, 10–11 mm diam, (when dry) shallowly 4- (or 8-)grooved and irregularly dimpled; calyx remnant small, narrow, with the 4 calyx lobes connivent.

Distribution ― The species is only known from the type.

Habitat & Ecology ― In Nothofagus dominated rain forest; c. 2000 m altitude; flowering and fruiting in September.

Field-note ― Fruit green.

Note ― The fruiting pedicel is remarkably long, 5–7 mm.