Origin and Habitat: South Africa (Eastern and Western Cape Provinces)

• Piaranthus geminatus var. foetidus (N.E.Br.) Meve
• Piaranthus foetidus N.E.Br.

• Piaranthus geminatus var. foetidus (N.E.Br.) Meve
• Piaranthus foetidus N.E.Br.
• Piaranthus foetidus var. diversus N.E.Br.
• Piaranthus foetidus var. multipunctatus N.E.Br.
• Piaranthus foetidus var. pallidus N.E.Br.
• Piaranthus foetidus var. purpureus N.E.Br.

• Piaranthus geminatus (Masson) N.E.Br.
• Caralluma geminata (Masson) Schltr.
• Obesia geminata (Masson) Haw.
• Podanthes geminata (Masson) G.Nicholson
• Stapelia geminata Masson
• Stisseria geminata (Masson) Kuntze
• Piaranthus barrydalensis Meve
• Piaranthus disparilis N.E.Br.
• Piaranthus disparilis var. immaculatus C.A.Lückh.
• Piaranthus globosus A.C.White & B.Sloane
• Piaranthus pillansii N.E.Br.
• Piaranthus pillansii var. fuscatus N.E.Br.
• Piaranthus pillansii var. incostans N.E.Br.

• Piaranthus geminatus subs. decorus (Masson) Bruyns
• Caralluma decora (Masson) Schltr.
• Obesia decora (Masson) Haw.
• Orbea decora (Masson) Steud.
• Piaranthus decorus (Masson) N.E.Br.
• Stapelia decora Masson
• Stisseria decora (Masson) Kuntze
• Piaranthus serrulatus (Jacq.) N.E.Br.
• Caruncularia serrulata (Jacq.) Don
• Obesia serrulata (Jacq.) Sweet
• Stapelia serrulata Jacq.
• Stisseria serrulata (Jacq.) Kuntze

Description: Piaranthus geminatusSN|18033]]SN|18024]] var. foetidus, best known as Piaranthus foetidusSN|18032]]SN|18039]], is a clumping and prostrate species that spread over the ground forming large cushions. This species shows a wide ecological amplitude, is very variable in colouration, and is the most common representative of Piaranthus.
Stems: Procumbent or ascending, tufted, 8-16(-20) mm wide by 2-5 (or under cultivation up to 12) cm long, divided in short squat ovoid or globose to short cylindrical, often clavate articles obtusely and sometimes indistinctly 4-(5-)angled, with 2-4 minute teeth along each angle, the tubercles tipped with a small acute apiculus having a minute tooth on each side at its base. Surface smooth or slightly rough, glabrous, light-green to grey-green, clouded or mottled with dull purple where exposed to the sun, tips faintly purple.
Flowers: 1 to 6 (but often 2) together near the top or at the middle of the stems, in a short inflorescence sometimes opening in pairs. Pedicels 6-18 mm long, erect, glabrous. Sepals 3-4 mmn. long, lanceolate or ovate-lanceolate, acuminate, with recurved tips, glabrous. Corolla ovoid to subglobose in bud, about (14-)18-22(-30 mm) in diameter when fully expanded, star-shaped, without a distinct tube, glabrous and green or tinted with purplish on the back, evenly pubescent, and velvety all over the inner face with short transverse purplish-crimson lines or lines and spots on a yellow ground, or sometimes the tips of the lobes are almost entirely purplish-crimson. Corolla lobes stout and fleshy, ovate or ovate-lanceolate, acute, convex above, concave beneath, from the recurving margins, 7-9 mm long, 3-5 mm broad, sometime basally fused, varying from ivory, to sand coloured, centrifugally increasingly patterned with brown-red dots or transverse lines (sometime condensed to a more or less plain colouration), densely hairy. Hairs 0.1-0.75 mm long, white, usually without but sometimes with a sparse ciliation of clavate vibratile hairs on the margins. Corona 2-3.5 mm long, 5-6 mm in diameter, yellow to orange. Outer corona-lobes 1.5-2 mm long, c 1 mm broad, closely incumbent upon the backs of the anthers, and equalling or shortly exceeding them, linear-lanceolate to oblanceolate, acute, entire or minutely denticulate at the apex, with raised lines and minute tubercles on the back, dorsally dilated at the base into a subquadrate crest 1.3-2 mm broad, truncate and denticulate-tuberculate on the top, deep orange-yellow, with the margins, the raised lines on the back and the tubercles of the crest all dark purple-brown. Flowers have a strong carrion-like odour or sweetish excrement odour, penetrating and perceptible at a short distance from the plant. Pollinia 0.55-0.7 x 0.3-0.4.
Blooming season: Produces numerous flowers simultaneously in October.
Fruits (paired follicles): 6-9 cm long.
Seeds: 4-5 by 2.5-3 mm.
Taxonomy remarks: The genus Piaranthus is a very confusing complex of extremely nearly related species with many intermediary forms growing together in many widespread localities and they are very difficult to distinguish. Also experienced botanist found difficulty to separate and classify reliably the various species and forms.
In particular Piaranthus geminatusSN|18024]]SN|18024]] var. geminatus is a very variable species which now also includes the former species Piaranthus globosus, Piaranthus disparilisSN|18039]]SN|18032]], and Piaranthus pillansiiSN|18024]]SN|18033]].

Notes: Pollination:
This plat are pollinated by flies (myiophilous pollination). Fly are attracted by olfactory stimuli, imitating dung or decaying organic (zoogenic or phytogenic) matter, together with mimetic colouration and, sometimes mimetic sculpturing. Nectar is present. The nectar mainly serves as optical attractant causing brilliance effects, and as visitor guide. However, nectar obviously is also a reward. In the pollination process flies carry pollinaria only at the distal parts of their proboscis, never on their legs. The pollinator spectra are similiar between of flowers in habitat and cultivated ones.

Bibliography: Major references and further lectures
1) N. E. Brown. “Flora Capensis”, Vol 4, page 518, 1909
2) Hermann Jacobsen “A handbook of succulent plants: descriptions, synonyms, and cultural details for succulents other than Cactaceae” Volume 1 Blandford Press, 1960
3) 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/Aug/2011
4) Doreen Court “Succulent Flora of Southern Africa” CRC Press, 01/Jun/2000
8) Focke Albers, Ulrich Meve "Illustrated Handbook of Succulent Plants: Asclepiadaceae: Asclepiadaceae," Volume 4 Springer, 2002
9) Alain Campbell White, Boyd L. Sloane "The Stapelieae: an introduction to the study of this tribe of Asclepiadaceae" S. E. Haselton, printer, 1933
10) John Robert Brown "Unusual Plants: 110 Spectacular Photographs of Succulents" Abbey Garden Press, 1954
11) Werner Rauh “The Wonderful World of Succulents: Cultivation and Description of Selected Succulent Plants Other Than Cacti” Smithsonian Institution Press, 1984
12) Victor, J.E. 2005. Piaranthus geminatus (Masson) N.E.Br. subsp. geminatus. National Assessment: Red List of South African Plants version 2014.1. Accessed on 2015/02/07

Cultivation and Propagation: It is an easy blooming plant when mature that require moderately watering through the growing season but enjoy plenty of water and some fertiliser in hot weather, this helps them to flower freely. Water more sparingly in winter according to temperatures. But, as with most asclepiads, it is unwise to leave them wet in cold weather. Winter care presents no problems at 5°C with plenty of light. 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.
Sun Exposure: Partial sun or light shade
Pest and diseases: Stapelia species vary in their susceptibility to rotting, but 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. If you do have problems with a stem or with basal rotting, you can reliably isolate the healthy parts, dry them off, and re-root them in moist compost.
Cultural Practices: Re-pot every 2 years
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.
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.