Planchonia Blume

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

Distribution

A small genus of eight species from the Andaman Islands, through Malesia to the Solomon Islands; two species in New Guinea: Planchonia careya (F.Muell.) R. Knuth and P. papuana R. Knuth.

Morphology General Habit

Trees to 40 m in New Guinea

Morphology Leaves Stipules

Stipules small, caducous

Morphology Leaves

Leaves spirally arranged, well-spaced along the twigs, margins entire or serrate-crenate

Morphology Reproductive morphology Inflorescences

Inflorescences terminal, erect few-flowered racemes or spikes; bracts and bracteoles sessile, small, caducous

Morphology Reproductive morphology Flowers

Flowers sessile, 4-merous; hypanthium campanulate to obconic, ribbed or smooth; calyx of 4 persistent, imbricate lobes; petals 4; stamens numerous in several whorls, shortly connate into a tube, inner whorl of staminodes, stamens and corolla caducous as a whole; disk intrastaminal, annular; ovary inferior, 3–4-locular; ovules longitudinally along the axis, numerous (c. 20 per locule); style filiform, exceeding stamens in length

Morphology Reproductive morphology Fruits

Fruit ovoid, ellipsoid to obovoid or globose, usually unribbed, with fibrous inner pericarp and leathery endocarp. Seeds (1–)3–15 in each locule, smooth or angular; embryo circinnate, cotyledons small, foliaceous.

Ecology

The two species of Planchonia in New Guinea are found in a variety of habitats including savannah forest, primary rain forest, riverine forests but also in secondary and disturbed habits from sea level to 300 m.

Recognition

The genus can be recognised by the well spaced leaves with finely serrate margins (sometimes appearing entire), the few-flowered racemose inflorescence, and the fruits with several seeds. The well spaced leaves are similar to Chydenanthus but that genus only has a single seed, and is a much rarer plant in New Guinea.