The genera of plants within the tribe Stapelieae are all to varying degrees stem succulents. Many of the species resemble cacti, though are not closely related, as an example of convergent evolution. The stems are often angular, mostly four-angled in cross-section, but in some species there are six or more, with some species of Hoodia having more than thirty angles. In size they vary from less than 2.5 cm/1" in length to over 2 m/6" tall. The leaves are in most species reduced to rudiments, sometimes hardened and thorn-like, arranged on bumps or tubercles on the angles. Some species, however, still have recognisable leaves, most notably the Indian species Frerea indica, and some members of Tridentea. Stapeliads are most abundant in warm, dry climates. In Africa, there are two separate regions where Stapeliads have most diversified: northeast Africa, and Southern Africa. Several species are endemic to the small island of Socotra off the Horn of Africa. The Arabian Peninsula, and most specifically the country of Yemen, contain another concentration of species. Several more are found in the drier parts of Pakistan, Afghanistan, India, Nepal, and Myanmar. A single species, Caralluma europea is found in Europe, in the very southern part of the Iberian peninsula. Stapeliads are often regarded as a climax group within the family because of their often structurally complex flowers. Certain aspects of these reproductive parts mirror the pollination systems in the Orchid family and represent a case of parallel evolution though both groups are quite unrelated and have developed similar, though not identical means to achieve the ultimate goal of pollination and therefore reproduction. Most stapeliads use flies as pollinators, that are attracted to odours resembling dung or rotting meat, emanating from the flowers. Many of the flowers also bear some physical resemblance to rotting animal carcasses, leading to their popular name of Carrion Flowers. However, not all stapeliads smell bad, or attract flies. Some species use beetles, bees, wasps, butterflies or moths as pollinators. Stapeliad flowers range in size from mere millimetres in species of Echidnopsis and Pseudolithos to those of Stapelia gigantea that can reach 40 cm/16" in diameter, and are some the largest of flowers to be found on any species of succulent.
The genus Huernia consists of perennial, stem succulents from Eastern and Southern Africa and Arabia, first described as a genus in 1810.
Ocimum is a genus of aromatic annual and perennial herbs and shrubs in the family Lamiaceae, native to the tropical and warm temperate regions of all 6 inhabited continents, with the greatest number of species in Africa. It is the genus of basil and the name is from the Ancient Greek word for basil, ὤκιμον (ṓkimon). Its best known species are the cooking herb cooking basil, O. basilicum and the medicinal herb tulsi, O. tenuiflorum.
Pennisetum is a widespread genus of plants in the grass family, native to tropical and warm temperate regions of the world. They are known commonly as fountaingrasses. Pennisetum is considered a synonym of Cenchrus in Kew's Plants of the World Online.
Acokanthera is a genus of flowering plants in the family Apocynaceae. It comprises 5 species and is generally restricted to Africa, although Acokanthera schimperi also occurs in Yemen. Its sap contains the deadly cardiotoxic glycoside ouabain. The sap is among the most commonly used in arrow poisons, including those used for poaching elephant.
Duvalia is a succulent plant genus in the subfamily Asclepiadoideae, in the family Apocynaceae (dogbane).
The Jouanin's petrel is a species of seabird in the family Procellariidae.
Lavrania is a monospecific genus of plant in family Apocynaceae, first described as a genus in 1986. It is native to Namibia.
- Lavrania haagneraePlowes - Namibia
Ozarba is a genus of moths of the family Noctuidae. The genus was erected by Francis Walker in 1865.
Edithcolea is a monotypic genus with a single species Edithcolea grandis. Once classified in the family Asclepiadaceae, it is now in the subfamily Asclepiadoideae of the dogbane family Apocynaceae. It is native to Africa and to the Arabian Peninsula.
Stapelianthus is a genus of flowering plants in the family Apocynaceae, first described as a genus in 1933. The entire genus is endemic to Madagascar and is concentrated in the far south of the island.
Pseudolithos is a genus of succulent flowering plants of the family Apocynaceae, indigenous to Somalia, Yemen and Oman.
Tavaresia is a genus of plants in the family Apocynaceae, first described as a genus in 1902. It is native to southern Africa.
- Tavaresia angolensisWelw. - Angola
- Tavaresia barklyi(Dyer) N.E.Br. - South Africa
- Tavaresia grandifloraBerger - South Africa
- Tavaresia meintjesiiR.A. Dyer - Limpopo
Piaranthus is a succulent plant genus in the subfamily Asclepiadoideae, in the family Apocynaceae.
Orbea is a genus of flowering plants of the family Apocynaceae, first described as a genus in 1812. It is native to Africa.
Notechidnopsis is a group of plants in the family Apocynaceae first described as a genus in 1985. It contains only one recognized species, Notechidnopsis tessellata, native to Cape Province in South Africa.
Rhytidocaulon is a plant genus in the family Apocynaceae, first described in 1962. It is native to northeastern Africa and the Arabian Peninsula
- Rhytidocaulon paradoxumP.R.O.Bally - Ethiopia
- Rhytidocaulon piliferumLavranos - Somalia
- Rhytidocaulon richardianumLavranos - Somalia
- Rhytidocaulon subscandensP.R.O.Bally - Somalia, Ethiopia
- Rhytidocaulon tortum(N.E.Br.) M.G.Gilbert - Arabia
John Jacob Lavranos was a Greek/South African insurance broker and botanist, with a special interest in succulents. The standard author abbreviation Lavranos is used to indicate this person as the author when citing a botanical name.
Peter René Oscar Bally was a Swiss botanical illustrator, botanist and taxonomist. The standard author abbreviation P.R.O.Bally is used to indicate this person as the author when citing a botanical name.
