Commemorating Dr Karl Peter Thunberg (1743–1822), Professor of Botany at Uppsala University.
Annual and perennial vines and shrubs. Leaves opposite, ovate to elliptic or lanceolate. Flowers in either terminal hanging clusters or solitary in the leaf axils, bright white, yellow, orange or blue, with 2 prominent leafy bracts enclosing the small calyx which is fused into a ring or with 10-15 teeth. Petal tube 5-lobed, curved and swollen. Stamens 4, in unequal pairs. Fruit a round, leathery capsule with a sword-shaped tip.
A genus sometimes placed in its own family, Thunbergiaceae. Grown mostly as colourful and ornate flowering vines in warmer regions.
Cuttings and seed.
Fertile stamens 4 and calyx in a ring or of 10-15 minute teeth within 2 showy bracts.
About 100 species from the tropics.
Source: (2002). Acanthaceae. In: . 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.