Ceratopetalum Sm.

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

Distribution

A genus of eight to ten species, mostly Australian, the range of one species extending to New Guinea: Ceratopetalum succirubrum C.T.White.

Morphology General Habit

Trees to 35 m tall (in New Guinea). Stipules interpetiolar, 1 pair per node, caducous

Morphology Leaves

Leaves opposite and decussate, trifoliolate, rarely bifoliolate (or unifoliolate in Australia), margin subentire to serrate, domatia absent

Morphology Reproductive morphology Inflorescences

Inflorescences axillary or terminal, paniculate, branching pattern opposite and decussate

Morphology Reproductive morphology Flowers

Flowers bisexual, 4–6-merous; calyx lobes valvate, reduplicate, accrescent; petals absent (in New Guinea); stamens included; disk annular; ovary semi-inferior, syncarpous, 2-locular, apically conical, ovules 4 per locule, styles spreading, persistent in fruit, stigmas punctate

Morphology Reproductive morphology Fruits

Fruit a woody, indehiscent pseudo-samara, with 4 wings formed by the accrescent calyx lobes

Morphology Reproductive morphology Seeds

Seeds 1 per locule.

Ecology

In New Guinea, Ceratopetalum is usually a canopy tree found in rain forests from sea level to about 1800 m.

Recognition

This species is used locally as a source of timber for building and carving and can be recognised by its trifoliolate leaves that often dry a light khaki green, the absence of petals, the semi-inferior, 2-locular ovary and by the 4-winged indehiscent fruit.