PNGTreesKey – Mastixiodendron smithii Merr. & L.M.Perry


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

Mastixiodendron smithii Merr. & L.M.Perry

Journal of the Arnold Arboretum Vol. 26: 255 (1945)

Family: Rubiaceae

Timber Group: Non-timber species

Field Characters: Large canopy tree (up to 40 m high) or Small sub-canopy tree; Bole cylindrical (up to c. 100 cm diam.); straight (bole up to c. 20 m long); buttresses buttresses present (buttresses up to c. 3 m high, rarely to 4 m.); spines spines absent; aerial roots aerial roots absent; stilt roots stilt roots absent; Bark pale brown or dark grey, rough, scaly or flaky; Subrhytidome (under-bark) green; less than 25 mm thick; bark blaze consisting of one layer; almost strongly aromatic or faintly to non-aromatic; pleasant (fruit-like); outer blaze white or yellow (pale (straw-coloured), markings absent, fibrous; inner blaze white or yellow (pale (straw-coloured), markings absent, fibrous; bark exudate (sap) present, colourless, not readily flowing (spotty), colour changing on exposure to air, to green, not sticky or sticky; 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 or winged (slightly (with lamina slightly extended down petiole), attached to base of leaf blade, not swollen or slightly swollen; leaves broadest at or near middle, 11.0-20.0 (-36.0) cm, 4.0-10.0 (-20.0) cm; symmetric, entire, not dissected or lobed, obtuse, venation pinnate, secondary veins open, not prominent, but visible, intramarginal veins absent; leaves lower surface pale green, upper surface dark green (glossy), indumentum (hairs) absent; absent; domatia absent; stipules present, joined, joined across twigs (slightly twisted), not encircling the twig or almost encircling the twig, leafy, not fringed, large (18-35 mm long), not persistent.

Flowers: Inflorescence axillary, flowers on a branched axis, cones absent; flowers bisexual, stalked, flowers with many planes of symmetry, (6.0-) 9.0-12.0 mm long, diameter small (up to10 mm diam.) (5-10 mm diam.); perianth present, with distinct sepals and petals whorls, inner perianth green (yellowish (towards base) or pale yellow; 4, free; stamens 4, present, free of each other, free of the perianth; ovary inferior, carpels joined (when more than one); styles solitary, 1.

Fruits: Infrutescence arranged on branched axis, fruit 35.0-50.0 (-70.0) mm long, 12.0-25.0 (-30.0) mm diam., green (probably immature), not spiny, fleshy, simple, indehiscent, drupe; seeds 1, much more than 10 mm long (20-25 mm long), not winged, narrow (longer than wide), seed 1-10 mm diam. (c. 10 mm diam.).

Distribution: Morobe, Eastern Highlands, Southern Highlands, Central & Northern.

Mastixiodendron smithii
Botanical records
in PNGplants database

Map details