Cleretum bellidiforme, previously Dorotheanthus bellidiformis Livingstone Daisy
One of South Africa’s most famous wildflower exports.
Cleretum bellidiforme is widely distributed in the Fynbos and Succulent Karoo Biomes in the winter rainfall area of the Western and Northern Cape.
This winter-growing, succulent annual, forms a low groundcover with several spreading branches. The green or maroon-tinted leaves are tongue- or spoon-shaped and more or less flat, with conspicuous raised, bladder-like, surface cells modified for water storage, which glisten in bright sunlight.
The slender, upright or leaning flower stalks are fleshy, grow up to 25 mm long and emerge from the branch tips. Numerous large, solitary, brightly coloured flowers, 20–30 mm in diameter, are produced, each having many, narrowly lance-shaped petals, which open widely in bright sunlight.
Petal colour is very variable, including white, cream-coloured, yellow, salmon-coloured, orange, pink, mauve, magenta or red, sometimes with contrasting white, maroon, yellow or light orange bases. The stamens are clustered together in the centre of the flower in 2 to 4 rows and have maroon filaments with purple or yellow anthers. The ovary is inferior, meaning that it appears below the stamens, and the ripe fruit is a capsule with expanding membranes, which bend outwards in wet weather. The flattened, 5-sided capsules are hard and dry when ripe, and comprise 5 compartments. The minute, irregularly shaped seeds are light brownish cream-coloured, with smooth surfaces.
Cleretum bellidiforme is a winter-growing annual adapted to cool, moist winters and hot, dry summers. The seeds germinate after the first autumn rains, followed by rapid vegetative growth in winter, and the plants flower from early to late spring (early August to mid-October, with a peak in September). The leaves are succulent and covered with raised, bladder-like surface cells which store water to nourish the plant during dry periods.
The flowers only open fully on warm, sunny days, remaining closed in cold or rainy weather. The flowers are self-fertile, but are visited by numerous insects which feed on the pollen, including monkey beetles, honey bees, drone flies and small, black, bee-flies.
The seed capsules ripen in summer, during which the seeds remain hidden within the hard and dry, closed capsules. The capsules are almost completely covered by membranes, with only a narrow opening between the membranes. Seed dispersal in these plants is termed ombrohydrochorous, meaning that it is activated by rain drops. The rain drops fall onto the covering membranes, resulting in them bending outwards and the seeds being forcefully ejected some distance from the plant, timed to coincide with autumn rains. As soon as dry weather returns, the membranes bend inwards to cover the remaining seeds. This mechanism ensures that the seeds germinate at the optimum time of year in autumn and early winter, and that they are protected from predators during the hot summer months. Only some of the seeds are released per rainy spell, thus preserving a reservoir of seeds.