Triangular Kisses

The vygie family, Aizoaceae, is best known for the dazzling displays found in the Little Karoo and up the West Coast. But there are a number of species found in true fynbos, which also have the glistening many petalled flowers. One of these, Oscularia deltoides, is a widespread species of rocky outcrops on the Table Mountain Sandstone. It loves to grow in rock crevices where there is minimal soil and has to tolerate extreme sun, heat and drought in the summer months. On account of this it has thick triangular greyish leaves, which store the water and help reflect the sunlight.

Oscularia deltoides (Aizoaceae)
Typical habitat of Oscularia deltoides, cascading down a rocky outcrop
Oscularia deltoides (Aizoaceae) leaves
Oscularia deltoides leaves forming mouth-like pairs

The species name reflects the shape of the leaves: “deltoides” means shaped like a triangle. The leaves are indeed quite triangular, both in outline and cross-section. The genus name has a more unusual derivation in that it comes from the Latin diminutive for mouth: “os” meaning mouth, “osculum” meaning little mouth. But in Latin, osculum is also the term for a kiss, presumably because one makes a little mouth when one kisses. This of course begs the question what on earth this succulent plant has to do with little mouths or kisses. The generic name was first coined in 1927 by Martin Schwantes (in an obscure German gardening magazine) and probably alludes to the shape of the newly emerging leaves. The leaves appear in pairs and are pressed together before gradually opening like a mouth. The margins of the leaves in Oscularia deltoides often have little teeth on them and so this may add to allusion of a little mouth, though not necessarily one that one would want to kiss.

The genus Oscularia is very closely related to the large Cape genus Lampranthus and at times the species have been considered to belong to the same genus. Now the genus is confined to only about 10 species (and even then, there is disagreement on which ones to recognise), many of them very localised to the West Coast mountainous areas. The species of Oscularia have leaves that are in general thicker than broad and a light grey in colour (usually as broad as thick or broader and grey to green in colour in Lampranthus). The flowers have five separate nectary glands (rather than in a ring in Lampranthus). Oscularia deltoides is by far the commonest and most widespread of the species in the genus. Oscularia deltoides is found from Tulbagh area south to the Cape Peninsula and Overberg and east as far as George.

Oscularia deltoides (Aizoaceae)
Typical pink flowers of Oscularia deltoides
Oscularia deltoides (Aizoaceae) white flowered
A rare white flowered form of Oscularia deltoides at Phillipskop which was flowering in October
Sometimes Oscularia deltoides grows in the smallest of cracks and then forms tight compact cushions

The toothed triangular succulent leaves, small pink (rarely white) flowers and habit of growing in rock crevices make Oscularia deltoides an easy plant to identify in the Overberg as the other species of Oscularia do not grow here.  At Phillipskop it is found on almost any rocky outcrop where there is enough soil and flowers in August (a white-flowered form has been found flowering in October.) On account of its preferred habitat, it is also a great plant for growing in a tub on a sunny patio and is easily propagated by cuttings.

Oscularia deltoides (Aizoaceae)
Oscularia deltoides on summit of Phillipskop

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