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

Neonauclea hagenii (Lauterb. & K.Schum.) Merr.

Journal of the Washington Academy of Science Vol. 5: 540 (1915)

Other Literature: C.E. Ridsdale, Blumea 230-234 (1989) Fig. 11-(plate; map)-22.

Family: Rubiaceae
Dicotyledon

Timber Group: Non-timber species

Field Characters: Small sub-canopy tree (10-20 m high) or Large canopy tree (up to 30 m high); Bole cylindrical (up to c. 50 cm diam.); straight (bole up to c. 12 m long); buttresses buttresses present (buttresses short); spines spines absent; aerial roots aerial roots absent; stilt roots stilt roots absent; Bark brown or grey, rough, slightly fissured, often pustular, or sometimes scaly or flaky, lenticels elongated vertically; Subrhytidome (under-bark) pink; less than 25 mm thick; bark blaze consisting of one layer; faintly to non-aromatic; outer blaze white, pink, yellowish brown, or pale yellow, markings absent, fibrous; inner blaze white, yellowish brown, pale yellow, or pink, markings absent, fibrous; bark exudate (sap) absent; terminal buds enclosed by leaves.

Indumentum: Complex hairs absent; stinging hairs absent; mature twig indumentum (hairs) absent.

Leaves: Leaves spaced along branches, opposite (in pairs, opposite one another on 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, (8.0-) 12.0-20.0 (-23.0) cm, (3.0-) 5.0-9.0 (-12.0) cm; symmetric, entire, not dissected or lobed, sub acute, venation pinnate, secondary veins open, not prominent, but visible, intramarginal veins absent; leaves lower surface pale green, upper surface dark green, indumentum (hairs) absent; absent; domatia absent; stipules present, joined, joined across twigs, not encircling the twig, leafy, fringed (minutely and finely hairy or with only a few minute scattered hairs), large (usually 8-16 mm long, rarely as long as 20 mm), not persistent.

Flowers: Inflorescence terminal, flowers arising from a single point, cones absent; perianth present, with distinct sepals and petals whorls, inner perianth cream-coloured or white; 5, some or partly joined; stamens 5, present (short), free of each other, joined to the perianth; ovary inferior, carpels joined (when more than one), locules 2; styles solitary.

Fruits: Infrutescence arising from single point (forming a globular fruiting head 25-30 mm diam., sometimes as small as 20 mm.), fruit pale brown, not spiny, non-fleshy, dehiscent (each fruitlet), capsule (each fruitlet splitting into 4 values); seeds 1 (per fruitlet; many per globular fruiting head), to about 5 mm long, winged (shortly at both ends), narrow (longer than wide) (somewhat bilaterally flattened), seed 1-10 mm diam. (c. 2 mm diam.).

Distribution: Morobe, Western (subsp. papuana) & New Britain.

Botanical records in PNGplants database Map details

Notes: Notes Two subspecies occur in Papua New Guinea, namely subsp. hagenii and subsp. papuana. Neonauclea hagenii subsp. hagenii has a flower with a glabrous corolla which is 9-12 mm long and mature fruiting heads (20-)25-30 mm diam., whereas, subsp. papuana has a hairy corolla which is 7-9 mm long, and mature fruiting heads 20-25 mm diam.