PNGTreesKey – Hopea iriana Slooten
Barry Conn (NSW) & Kipiro Damas (LAE).
Guide to trees of Papua New Guinea
Copyright held by the authors, National Herbarium of New South Wales, and Papua New Guinea National Herbarium
Reinwardtia Vol. 2: 28 (1952)
Timber Group: Major exportable hardwood
Field Characters: Large canopy tree (30-40 m high); Bole cylindrical (to slightly spurred, c. 0.6 m diam.); straight (bole up to 30 m long); buttresses rarely buttresses present or usually buttresses absent; spines spines absent; aerial roots aerial roots absent; stilt roots stilt roots absent; Bark dark grey or brown, slightly rough or smooth, scaly or flaky or fissured; Subrhytidome (under-bark) brown; less than 25 mm thick, 15.0 (c.); bark blaze consisting of one layer; faintly to non-aromatic; outer blaze pink or pale brown, markings absent, fibrous; inner blaze pink or pale brown, markings absent, fibrous; bark exudate (sap) absent; terminal buds not enclosed by leaves.
Indumentum: Complex hairs absent; stinging hairs absent; mature twig indumentum (hairs) absent (small lenticels present).
Leaves: Leaves spaced along branches, spiral (leaves occurring singly at a node and arranged spirally up the branchlet), simple (a leaf composed of a single blade); petiole present, not winged, attached to base of leaf blade, not swollen; leaves broadest at or near middle or broadest below middle, 8.0-11.0 cm, 3.0-4.0 cm; symmetric (mostly (slightly asymmetric), entire, not dissected or lobed, acuminate, venation pinnate, secondary veins open, prominent, intramarginal veins absent; leaves lower surface pale green, upper surface dark green, indumentum (hairs) absent; absent; domatia absent; stipules absent.
Flowers: Inflorescence terminal or axillary, flowers on a branched axis, cones absent; flowers bisexual, stalked, flowers slightly asymmetric or with one plane of symmetry, 4.0-5.0 mm long, diameter small (up to10 mm diam.) (c. 5 mm diam.); perianth present, with distinct sepals and petals whorls, inner perianth white or cream-coloured; 5, some or partly joined (at base); stamens 10 (c.), present (broad at base), free of each other, joined to the perianth (at base and falling with petals); ovary superior, carpels joined (when more than one), locules 2; styles solitary, 1 (thickened to form a stylopodium).
Fruits: Infrutescence arranged on branched axis, fruit 10.0 (c.) mm long, 8.0 (c.) mm diam., brown, not spiny, non-fleshy, simple, dehiscent, capsule (often referred to as a nut, but splitting at germination into more or less 3 regular valves); seeds 1, about 10 mm long (c. 8 mm long), not winged, broad (as wide as long), seed 1-10 mm diam. (c. 8 mm diam.).
Distribution: West Sepik, East Sepik, Morobe, Western & Milne Bay.
in PNGplants database