PNGTreesKey – Tristiropsis acutangula Radlk.


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

Tristiropsis acutangula Radlk.

Sitzungsberichte der mathematisch-physikalischen Classe der K. b. Akademie der Wissenschaften zu München Vol. 20: 248 (1890)

Other Literature: P.W. Leenhouts, Flora Malesiana, Series 1 743-745 (1994) Fig. 82 (d & e).

Family: Sapindaceae

Timber Group: Minor hardwood

Field Characters: Large canopy tree (up to 35 m high, rarely to 53 m); Bole cylindrical (up to c. 50 cm diam.); straight (bole up to 30 m long); buttresses buttresses present (buttresses mostly up to 1 m high, sometimes to 3 m); spines spines absent; aerial roots aerial roots absent; stilt roots stilt roots absent; Bark dark brown, slightly rough or mostly smooth, slightly pustular, lenticels rounded/swelling (numerous); Subrhytidome (under-bark) red; less than 25 mm thick, 6.0-8.0; bark blaze consisting of one layer; faintly to non-aromatic; outer blaze yellow (pale (straw-coloured) or pale pink, markings absent, granular without splinters; inner blaze yellow (pale (straw-coloured) or pale pink, markings absent, granular without splinters; bark exudate (sap) absent; terminal buds not enclosed by leaves.

Indumentum: Complex hairs absent; stinging hairs absent; mature twig indumentum (hairs) present, hairs dense to sparse.

Leaves: Leaves spaced along branches, spiral (leaves occurring singly at a node and arranged spirally up the branchlet), compound (a leaf made up from two or more leaflets); petiole present, not winged, attached to base of leaf blade, swollen (at base); leaves pinnate (unbranched with more than three leaflets); petiolule not swollen to swollen (slightly (at base); rachis present, absent, absent; leaves without a terminal leaflet (the number of leaflets even - paripinnate), broadest at or near middle to broadest below middle, 5.0-18.0 cm, (1.5-) 2.0-8.0 cm, leaflets opposite, symmetric; venation pinnate, secondary veins open, not prominent, but visible, intramarginal veins absent; leaves lower surface pale green, upper surface green, indumentum (hairs) absent to present (in axils of secondary veins and mid-vein of lower surface), indumentum (hairs) dense to sparse; absent; domatia absent to present, scattered along midrib (hairs in axils of secondary veins and mid-vein of lower surface appearing like domatia); stipules absent.

Flowers: Inflorescence axillary, flowers on a branched axis, cones absent; flowers bisexual, stalked, flowers with many planes of symmetry, 2.5-3.5 mm long, diameter small (up to10 mm diam.) (c. 3 mm diam.); perianth present, with distinct sepals and petals whorls, inner perianth white or pale yellow or cream-coloured; 5, free; stamens 8 (c.), present, free of each other, free of the perianth; ovary superior, carpels joined (when more than one), locules rarely 3-5; styles solitary, 1.

Fruits: Infrutescence arranged on branched axis, fruit 20.0-30.0 mm long, dark yellow, green, or brown, not spiny, fleshy, simple, indehiscent, drupe; seeds 1, much more than 10 mm long, not winged, broad (as wide as long), seed more than 10 mm diam.

Distribution: West Sepik, East Sepik, Madang, Morobe, Western, Gulf, Central, Northern, Papuan Islands & Manus.

Tristiropsis acutangula
Botanical records
in PNGplants database

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