Didelta is a genus of shrubs of up to 1 or 2 meter high, with two known species in the daisy family. Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and are surrounded by an involucre, consisting of in this case two whorls of bracts, which are almost free from each other. The 3–5 outer bracts are protruding and triangular in shape, the inner about twice as many are lance-shaped and ascending. In Didelta, the centre of the head is taken by 3–5 clusters of bisexual yolk yellow disc florets, sometimes divided from each other by male disc florets, and is surrounded by one complete whorl of infertile yolk yellow ray florets. The common base of the flowerhead swells around the developing fruitlets, become woody and breaks into segments when ripe. The fruitlets germinate within this woody encasing. The species of the genus Didelta can be found in Namibia and South Africa. The genus is called salad thistle in English and slaaibos in Afrikaans.
Didelta
Fruiting head of kusslaaibos, Didelta carnosa
Type specimen of Didelta tetragoniaefolia, colored etching by Pierre-Joseph Redouté published in 1784
In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word succulent comes from the Latin word sucus, meaning "juice" or "sap".
Succulent plants have thickened stems, or leaves, such as this Aloe.
The center rosette of (Aloe polyphylla)
A collection of succulent plants, including cacti, from the Jardin botanique d'Èze, France
Succulents, such as these Adromischus marianae, Crassula deceptor and Conophytum, share an affinity for arid, fast-draining soils, often growing directly on rocks