Protium Burm.f.

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution

A genus of about 180 species, mostly from the Neotropics, but also in Madagascar and tropical and subtropical Asia; a single species in New Guinea: Protium macgregorii (F.M.Bail.) Leenh.

Morphology General Habit

Evergreen trees, sometimes shrubs to 25 m tall, buttresses often present

Morphology Leaves Stipules

Stipules absent

Morphology Leaves

Leaves imparipinnate, pulvinus always present at apex of terminal petiolule and usually also on lateral petiolules, margins entire, tips of leaflets often mucronate

Morphology Reproductive morphology Inflorescences

Inflorescences axillary, paniculate

Morphology Reproductive morphology Flowers

Flowers unisexual or possibly bisexual, 5-merous (in New Guinea), receptacle flat; sepals fused for about half their length (in New Guinea), persistent in fruit; petals free, valvate; stamens twice as many as petals, similar in size in male and female flowers; disk intrastaminal, annular; ovary 4–5-locular, style sometimes with short stylar branches

Morphology Reproductive morphology Fruits

Fruit dehiscent by 1–5 valves, pericarp fleshy, pyrenes 2–4, each covered with a spongy pseudaril.

Ecology

In New Guinea Protium has usually been collected from secondary forests, but also occurs in open savannahs and has an altitudinal range from 50–800 m.

Recognition

The genus can be recognised by the leaflets which are acuminate and mucronate at the apex, the 5-merous flowers with valvate petals and a flat receptacle, and the fleshy fruit which dehisces by valves, exposing the 4 or 5 stony pyrenes, each covered with a white, spongy arillate structure.