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

Polyosma forbesii Valeton ex Lauterb.

Nova Guinea Vol. 8: 821 (1912)

Field Characters: Small trees 10 m high. Bole cylindrical 10-15 cm diam.; straight bole 1-2 m long; buttresses absent; spines absent; aerial roots absent; stilt roots absent. Bark pale brown, rough, strongly fissured with fissures broad; subrhytidome dark red; bark thickness <25 mm thick, 4.0-6.0 mm thick; blaze consisting of one layer; faintly to non-aromatic; outer blaze pale black, markings absent, slightly fibrous; inner blaze pale brown, markings absent, slightly fibrous; exudate absent. Terminal buds not enclosed by leaves; complex hairs absent; stinging hairs absent; mature twig without hairs.

Leaves: Less often spaced along branches <internodes readily visible> or clustered at end of branches <internodes indistinct>. Leaves opposite, simple; petiole present 12-18 mm long, not winged, attached to base of leaf blade <not peltate>, not swollen; lamina broadest above middle or broadest at or near middle, 15.0-20.0 cm long, 5.0-7.0 cm wide; lamina symmetric, margin entire, not dissected or lobed, apex slightly acuminate, venation pinnate <secondary veins arising from the midrib along its length>, secondary veins open <spaced far apart to easily see tertiary veins>, prominent, intramarginal veins absent; lower surface dull green, upper surface green, hairs present lower surface or absent on upper surface, dense; oil dots absent; domatia absent; stipules absent.

Flowers: Inflorescence axillary <from between a leaf and branch> in distal leaf axils. Flowers on an unbranched axis; flowers bisexual, stalked, with many planes of symmetry <actinomorphic>, 10.0 mm long, small (< or =10 mm diam.) 3-5 mm diam.; perianth present densely hairy (at least in bud), with distinct sepals and petals petals narrow, white or pale yellow; inner perianth 4, some or partly joined; stamens 4, filaments present, free of each other, free of perianth; ovary inferior <seated below the petals and sepals; epigenous>, carpels joined (when more than one) <syncarpous>, locules 2; styles solitary <including joined together>, 1.

Fruits: Fruits arranged on unbranched axis. Fruit 10-12 mm long, 6.0-8.0 mm diam., fruit green or red maroon, not spiny hairy with off-white hairs, fleshy, simple, indehiscent, drupe. Seeds 1, to about 5 mm long 5-6 mm long, not winged, as wide as long, 1-10 mm diam. 4-5 mm diam.

Distribution: Morobe.

Botanical records in PNGplants database Map details

Notes: Polyosma has previously been placed in the Cunoniaceae, Escalloniaceae, Grossullariaceae and Saxifragaceae families.