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Accepted Scientific Name: Orbea paradoxa (I.Verd.) L.C.Leach
Excelsa Taxon. Ser. 1: 55 1978
Origin and Habitat: Orbea paradoxa has been recorded mostly on coastal plains in southern Mozambique and around Pongola in the south-eastern Transvaal. It extends further into northern KwaZulu-Natal, in eastern Swaziland and near Komatipoort in Mpumalanga.
Habitat and ecology: Arid bushveld.
Altitude range: 20 - 300 metres above sea level.
ENGLISH: Paradoxical orbea
ZULU (isiZulu): Umanhlangwane
Description: 0rbea paradoxa (Stultitia paradoxa) is a rhizomatous, leafless dwarf perennial succulent species, forming small clumps of erect stems above ground that, like those of Orbea maculate, spreads by horizontal underground rhizomes. The long-toothed stems are Orbea-like in character, but the small, campanulate flowers with dark red annulus at the mouth of the tube (6.5 mm deep) lean more to-wards the genus Pachycymbium. This led to many disputes among botanists in deciding its generic position, and finally Leach placed it in a section of its own in Orbea.
Derivation of specific name: The specific epithet is derived from the Latin for unexpected or unusual.
Stem: Extremely rhizomatous. Above ground stems mottled, 4-angled erect, fairly slender with prominent tubercles along the angles. These tubercles are distinctly flattened towards the apex, and this flattened part constitutes the leaf-rudiment. Towards the base of this flattened area the margins are extended into 1-3 spreading denticles (toothlets) on each side (i.e., up to 6 denticles per tubercle). This multitude of small denticles around the apex of the tubercle immediately distinguishes this species from any other in the area.
Flowers: Solitary or in pairs. The flowers of O. paradoxa are fairly small but make up for this by having an unusual colouring and a very foul smell of rotten meat. The corolla is campanulate with a dark red annulus at the mouth of the shallow tube (6.5 mm deep) which, from the outside of the flower, has a more or less funnel-like shape, the annulus often rises out of the tube and projects inwards as a thin wall, thereby considerably constricting the mouth of the tube. The interior of the corolla is greenish-white to yellowish with reddish purple markings, smooth and quite shiny, except for fine papillae near the tips of the lobes and few to many short, fleshy hairs in the base of the tube, while the margins of the corolla lobes have a distinct fringe of purple, spoon-like vibratile cilia (hairs), the cilia are densest at the sinuses between the lobes, at which point there is also a short, fleshy spur. This whole arrangement, with its colouring and evil smell, somewhat resembles a festering wound on the skin of a mammal.
Blooming season: Flowering time is very dependent on the rains, as it grows in heavy soils; usually November-January in habitat.
Bibliography: Major references and further lectueres
1) Court, “Succulent flora of southern Africa”, A.A. Balkema, Rotterdam 1981
2) James Cullen, Sabina G. Knees, H. Suzanne Cubey “The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass” Cambridge University Press, 11 August 2011
3) John Hunter Thomas “Systematic Botany Monographs” American Society of Plant Taxonomists, 2002
4) David Hardy, Anita Fabian, Gerrit Germishuizen “Succulents of the Transvaal” Southern Book Publishers, 1992
5) Fl. Pl. South Africa 17: t.677 (1937)
6) List South. African Succ. Pl. : 27 (1997)
7) Syst. Bot. Monogr. 63: 151-153 (2002)
8) Victor, J.E. & Scott-Shaw, C.R. 2005. “Orbea paradoxa (I.Verd.) L.C.Leach.” National Assessment: Red List of South African Plants version 2014.1. Accessed on 2015/02/24
Cultivation and Propagation: Orbea paradoxa is an easily grown stapeliad, suited to hanging baskets as well as pots. It grow well in light gritty soil with a very liberal drainage. They should at all times sparingly watered (best rain water with some occasional fertiliser), and in winter time they hardly require any. They require outdoor culture, or a warm close greenhouse, while growing in the early part of summer, and afterwards may be ripened and kept in a greenhouse; but as they bloom chiefly in autumn, warmth is desirable to enable them to expand their flowers. They are also most attractive in a hanging pot with their trailing segments With numerous fleshy (non-hurtful) teeth. Some collectors enjoy the long, snake-like stems induced by an excess of water.
Spring: When winter ends and they begin to grow again, they will require much water and soaking the pots will no longer put the plants at risk for rot. In the spring they will grow well in partial shade and leaving them out in the rain may provide them with the water they need.
Summer: In the summer months they will tolerate heavy rain, but will be just as happy if the season is dry. It's best to sort out the stems while the plants are resting in the summer before they begin their autumnal growth cycle. They will tolerate very hot weather outdoors as long as they are kept in filtered light and this will encourage them to flower in the Autumn. They also enjoy some fertiliser. Moving the plants as they are developing buds may cause them to spontaneously abort the flowers all together.
Autumn: In the fall keep them outdoors until the night time temperatures drop below the 5°C.
Winter: Winter care presents no problems at 5°-10° C with plenty of light. As soon as they are flowered be sure to take extra precautions to keep them dry, because damp cool conditions when the plants are resting is an invitation to fungal infections, but - according to temperatures –some occasional lit watering may be useful.
Potting medium: Since roots are quite shallow, use a cactus mix or add extra perlite or pumice to regular soil potting soil. A gritty, very free-draining compost is suitable, and clay pots help the plants to dry out between watering. Re-pot every 2 years.
Pest and diseases: Orbea are generally fairly easy to grow, especially if kept pest-free. They are very susceptible to stem and root mealy bugs, and damage from these may well initiate fungal attack. Any time when there is a dead or dying stem in the pot it is important to remove it immediately and completely before other healthy stems can become ill too, isolate the healthy parts, dry them off, and re-root them in new compost.
Propagation: Easiest with stem cuttings. Allow cuttings to dry a day before planting. Stems must be laid (Not buried) on gritty compost and will then root from the underside of the stems. It can also be increased from seeds sowing in spring in moist, sandy peat moss. Barely cover seeds. Seeds germinate quickly. In any season it's best to lay the stems out for several days before replanting them and then pot them only in dry soil and withhold any water until they begin to shrivel or start growing again.
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