Description: Trees, shrubs or annual herbs, branchlets often orange, brown or red; dioecious or monoecious.
Leaves alternate, simple, entire, often succulent; stipules small.
Inflorescences axillary or terminal, racemes or panicles, or flowers solitary. Flowers unisexual, ± actinomorphic, small. Calyx shallowly cupular, lobed or entire, persistent in fruit. Corolla absent. Male flowers with 7–100 stamens, either in several concentric whorls or in 1 whorl surrounding a central disc; anthers almost sessile, 2-locular, dehiscing by longitudinal slits. Female flowers with solitary carpel or carpels 2–many and fused, sometimes around a central column; ovule 1 per carpel; styles 1 per carpel, free or shortly united with one another.
Fruit a dry or succulent schizocarp, achenes or a syncarp; carpels often separating before shedding seeds; seeds usually ± U-shaped, aril translucent. Most species are plants of disturbed areas or fire-opportunists; usually in drier regions.
Distribution and occurrence: World: 4 genera, 17 species, endemic Australia. Australia: all States.
Angiosperm Phylogeny Website (Family: Gyrostemonaceae, Order: Brassicales)
Text by G. J. Harden
| ||Key to the genera|| |
|1||Leaves linear to broad-ovate, if lamina linear-lanceolate then more than 3 cm long, flat, mostly petiolate; small trees; fruit bell-shaped; carpels dehiscing on inner margin; flowers in racemes or panicles, pedicel more than 8 mm long||Codonocarpus|
|Leaves linear to narrow-lanceolate, mostly less than 3 cm long, often more or less terete, sessile; erect herbs, small shrubs or rarely small trees; fruit more or less globose; carpels dehiscing on outer margin; flowers solitary, pedicel less than 7 mm long||Gyrostemon|