Aistopetalum Schltr.

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

Distribution

A genus of two species endemic to New Guinea: Aistopetalum multiflorum Schltr. and A. viticoides Schltr.

Morphology General Habit

Canopy trees to 40 m tall

Morphology Leaves Stipules

Stipules interpetiolar, 1 pair per node, caducous

Morphology Leaves

Leaves opposite and decussate, imparipinnate, lateral leaflets subopposite, terminal leaflet usually larger than laterals, glabrous or almost so, margins serrate to subentire, domatia absent

Morphology Reproductive morphology Inflorescences

Inflorescences axillary, paniculate, branching pattern opposite and decussate

Morphology Reproductive morphology Flowers

Flowers bisexual, 4–7-merous; calyx lobes valvate; petals absent; stamens barely exserted; disk annular, sometimes lobed; ovary superior, syncarpous, 4–7-locular, ovules 1 per locule, styles conical, shorter than ovary, free or fused to form a single stylar surface, stigmas punctate

Morphology Reproductive morphology Fruits

Fruit a drupe topped by small stylar remnants or with a central depression, containing a coriaceous to woody endocarp

Morphology Reproductive morphology Seeds

Seeds 4–8, oblong.

Ecology

Aistopetalum is found in rain forests from lowland to lower montane areas, up to 2200 m.

Recognition

The genus can be recognised by the imparipinnate leaves with subopposite leaflets, the 4–7-merous flowers that lack petals, the 4–7-locular ovary and the drupaceous fruit.