Origin and Habitat: Coastal regions of the Cape Province, South Africa.
Habitat and Ecology: Piaranthus pillansiiSN|18033]]SN|18033]] usually grows interlocked with the stems of shrubs, as is often seen with most members of the Stapelieae.

• Piaranthus pillansii 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

• 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.

Description: Piaranthus pillansiiSN|18033]]SN|18033]] is one of the morphological or geographical form of the very variable Piaranthus geminatusSN|18032]]SN|18024]]. It is a low growing succulent plant that grows in mats. It is distinguished by it flowers typically greenish yellow, pale yellow or very pale-reddish, without (or with very fine) red spots. The starry flowers up to 3-4 cm wide appears in groups of 2-3 and have a strong scent of Valerian. The corona is usually yellowish-green in colour and this colour extends to the base of the corolla-tube. The flowers in the genus have tightly replicate corolla lobes (folded back on themselves).
Stems: 1-4 cm long (to 10 cm in cultivation), 10-16 mm thick, decumbent, oblong or somewhat clavate-oblong, very obtusely 4- (rarely 5-) angled or subcylindric, glabrous, dull light green, mottled or tinted with dull purple, angles not or scarcely tuberculate, with very minute apiculus-like teeth, having a more minute tooth on each side at the base.
Flowers: Usually in pairs at the middle or upper part of the young stems, erect; pedicels 6-8 mm long, glabrous; sepals 4 mm long, lanceolate, acute, glabrous; corolla rotate, lobed nearly to the base, 30-36 mm in diameter. Lobes very spreading, 12-16 mm long, about 4-5 mm broad at the base, narrowly lanceolate, acute, convex from the margins being recurved, glabrous on the back, very shortly velvety-puberulous on the inner face, not ciliate, dull greenish-yellow, pale yellow or very pale-reddish without spots; corona-lobes rather more than 2mm long, closely incumbent upon the backs of the anthers and exceeding them, with their tips crossing each other but not becoming erect, lanceolate, acute, entire or somewhat 3-toothed at the apex, produced at the base into a truncate or very obtuse dorsal crest, minutely tuberculate or with ridges on the top, and the dorsal margin neither acute-edged nor toothed, yellow, without markings.
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|18037]]SN|18024]] var. geminatus is a very variable species which now also includes the former species Piaranthus globosusSN|18024]]SN|18037]], Piaranthus disparilisSN|18024]]SN|18032]], and Piaranthus pillansiiSN|18033]]SN|18033]].

Bibliography: Major references and further lectures
1) N. E. BROWN.”Flora Capensis” Vol 4, page 518, 1909
2) Werner Rauh “The Wonderful World of Succulents: Cultivation and Description of Selected Succulent Plants Other Than Cacti” Smithsonian Institution Press, 1984

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.