PNGTrees – Macaranga albescens Perry

 

Barry Conn (NSW) & Kipiro Damas (LAE).
Copyright held by the authors, Royal Botanic Gardens and Domain Trust, and Papua New Guinea National Herbarium

Macaranga albescens Perry

Journal of the Arnold Arboretum Vol. 34: 244 (1953)


Family: Euphorbiaceae
Dicotyledon
No. Non-timber species

Field Characters: Small trees or large trees 20 m high. Bole cylindrical to slightly fluted, about 25 cm diam.; straight bole about 14 m long; buttresses absent; spines absent; aerial roots absent; stilt roots absent. Bark brown; blaze consisting of one layer; outer blaze red, granular without splinters brittle; inner blaze red, granular without splinters brittle; exudate present, colourless watery, spotty, not changing colour on exposure to air, sticky. Terminal buds not enclosed by leaves; complex hairs absent; stinging hairs absent; mature twig hairy hairs minute or mature twig without hairs note: new leaves and inflorescence densely hairy.

Leaves: Spaced along branches <internodes readily visible>. Leaves spiral, simple; petiole present 2-10 cm long, not winged, attached to surface of leaf blade <peltate>, swollen <at tip, or base, or both> lamina broadest below middle, (5.0-) 12.0-14.0 cm long, (3.5-) 10.0-11.0 cm wide; lamina symmetric, margin entire, not dissected or lobed, apex shortly acuminate, venation trinerved <three large veins arising from the base>, palmate <more than three large veins arising from the base> mostly with 5-7 primary veins, or pinnate <secondary veins arising from the midrib along its length> on distal part of leaf, secondary veins open <spaced far apart to easily see tertiary veins>, prominent, intramarginal veins present; lower surface green often silvery, upper surface green, hairs present, sparse; oil dots absent; domatia absent; stipules absent (by misinterpretation) because soon falling off or present, free <from one another>, laterally placed <whether free or joined>, not encircling the twig, hair-like or leafy very narrowly ovate, not fringed, small <not easily visible to the eye> about 4 mm long, not persistent.

Flowers: Inflorescence axillary <from between a leaf and branch>. Flowers on a branched axis; flowers unisexual, with male and female flowers on the same plant <monoecious>, flowers stalked, with many planes of symmetry <actinomorphic>, 1.0-2.0 mm long, small (< or =10 mm diam.) about 1.5 mm diam.; perianth present, petals absent or with all sepals and/or petals (hence tepals) similar (by misinterpretation), pale yellow; inner perianth 2-4 (2-3 male flowers; 3-4 female flowers), some or partly joined; stamens 5-11 (male flowers), free of perianth; ovary superior <seated above petals and sepals; hypogenous>, carpels solitary <monomerous>, locules 1; styles solitary <including joined together>, 1 (hairy).

Fruits: Fruits arranged on branched axis. Fruit c. 6 mm long, c. 6.0 mm diam., fruit green silvery, not spiny but surface with irregular projections, simple broadest below middle, dehiscent, capsule. Seeds 1, to about 5 mm long about 4 mm long, as wide as long, 1-10 mm diam. about 4 mm diam.

Distribution: Morobe, Western Highlands, Eastern Highlands & Central.


Macaranga albescens
Botanical records
in PNGplants database

Map details