Orbeanthus Leach

Named for the genus Orbea and the Greek 'anthos', flower; for the Orbea like flowers. There are but two species in the genus Orbeanthus conjunctus and Orbeanthus hardyi. Both species are found in in the Northern Province of South Africa and O. hardyi is also found in Mpumalanga.  Both species are dwarf branching stem succulents which easily root along their length.  They also tend to be fragile and are easily broken at their joints and form separate plants.

Whilst being closely related to  Orbea, Orbeanthus shares many affinities with the Madagascan  genus Stapelianthus Leach.  Peter Bruyns includes Orbeanthus in the genus Orbea whilst Ulrich Meve maintains it as a separate genus citing the vegetative stems and differences in corona structure.

Oxypetalum R.Brown

In the sub family Oxypetalinae this South American genus of non succulent perennial sub-shrubs and twiners, numbers around 150 species.  The name derives from the Greek, oxys; sharp and petalon; a petal.

Oxypetalum banksii

Grown from seed IAS1691  collected at Marambaia Island, Rio de Janeiro, Brazil this species is a vigorous climber that needs plenty of water during summer when it produces masses of attractive flowers over a long period.

Oxypetalum coeruleum

Originating in Brazil and Uruguay this may well be the only blue flowered asclepiad.  The flowers deepen to a purplish hue with age.  The weakly twining sub shrubs can be grown in tubs outdoors in the Northern hemisphere but should be cut back to two buds and over-wintered in a conservatory or greenhouse.

 

Pectinaria Haworth

From the Latin 'pectinarius', comb-; for the comb-like processes of the corona.  The genus consists of perennial, mostly decumbent, mat forming plants with 6 - ribbed stems.  In 2003 Darrel Plowes revised this genus raising the four subspecies of Pectinaria articulata to species level, creating a new species Pectinaria flavescens and transferring the former species Pectinaria longipes and P. maughanii to a new genus Vadulia.

Pectinaria articulata 

Found only in the Northern Cape Province, in an area north west of Sutherland.

Pectinaria asperiflora

With an equally narrow distribution this species is found only in the Western Cape Province in an area from the eastern margins of the Great Karoo to the Little Karoo south of Laingsburg.

Pectinaria namaquensis

As the species name implies this is found in the Little Namaqualand area of the Northern Cape Province. The flower colour is variable being either purple-red or the greenish yellow shown here on a plant found at Vaalputs, near Springbok.

Pergularia L.

A non-succulent genus of around 80 species many of which are scrambling or twining plants. A number are used extensively in local medicinal remedies.

Pergularia daemia

This perennial twining species with hairy stems and leaves has a wide spread distribution in Africa being found in Cameroon, Botswana, Egypt, Ethiopia, Gambia; Ghana; Liberia; Nigeria; Senegal; Namibia; South Africa; Swaziland, Tanzania. It is also found in Asia in India; Pakistan; Sri Lanka Myanmar Malaysia. the plant pictured was grown from seed IAS1248 from central Botswana.

Periploca L.

A genus of around 120 species of woody vines of warm regions of the Old World.

Periploca gracilis

An attractive perennial species from Cilicia in Turkey