Commemorating Jan Zier (d. 1796), Polish cryptogamic botanist.

Shrubs or small trees. Leaves opposite or appearing whorled, mostly of 3 palmate leaflets, rarely only 1; margins entire or with glandular teeth, the terminal leaflet largest. Flower clusters axillary. Flowers bisexual, the calyx 4-lobed, united at the base. Petals 4, free, not persistent. Stamens 4, free, opposite the sepals, the disk with 4 prominent gland-like lobes alternating with the petals. Ovary of 4 basally united carpels, each with 2 ovules; styles united. Fruit of 1-4 units, the seed dispersed explosively.

Grown for the flowers and foliage.

This genus is currently under revision.

Petals 4; stamens 4; disk with 4 prominent gland-like lobes alternating with the petals.

About 61 species from Australia (60 species endemic) and New Caledonia (1 species).

Source: Spencer, R. (2002). Rutaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.