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Cotyledon | |
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Cotyledon orbiculata (grey variety) | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Saxifragales |
Family: | Crassulaceae |
Subfamily: | Kalanchoideae |
Genus: | Cotyledon Tourn. ex L. 1753 |
Species | |
See text |
Cotyledon is one of some 35 genera of succulent plants in the family Crassulaceae. Mostly from Southern Africa, they also occur throughout the drier parts of Africa as far north as the Arabian Peninsula. Ten of its species are mostly confined to South Africa, where unlike Tylecodon , they occur commonly in both the winter and summer rainfall regions. [1] They may be found on coastal flats and rocky hillsides, or as cremnophytes on cliff faces. Their decussate, evergreen leaves are highly variable in shape, even within some species, but the flowers, apart from colour, are very similar. [1]
Members of the genus are shrublets, generally succulent, with fleshily woody, brittle stems and persistent succulent leaves. [2] [3]
The leaves are opposite. Leaf pairs generally are oriented at 90 degrees to their preceding and following pairs, as is common in the family Crassulaceae, but the leaf habit differs from say Tylecodon (in which the leaves are borne in spirals and are deciduous).
The flowers are pendulous and tubular, borne at the tips of stout, rather long peduncles, mainly in short cymes. Calyx 5-partited, corolla 5-lobed. Petals united in a tube or urn that generally is longer than broad, their triangular tips more or less pointed and recurved, 10 stamens arising from corolla near base and projecting or nearly projecting from the corolla. Gynoecium comprises 5 carpels, nearly or quite free, each carpel tapering into a slender style with an obliquely capitate stigma. Each carpel contains many small (typically less than 1 milligramme when ripe) globular, brown seeds.
Together with Tylecodon , Kalanchoe and Adromischus it forms a sister clade to the family's basal Crassula clade. [1] Until the 1960s, some 150 species were included in the genus Cotyledon, [4] but subsequently it was split into at least Adromischus , Dudleya , Rosularia , and Tylecodon , leaving probably less than two dozen species in Cotyledon. [5] Of these, about four are characteristically fynbos plants. [6]
Most plants in the genus, and those that used to be included in the genus Cotyledon, are poisonous, even dangerously so. Some have been implicated in stock losses among goats, pigs and poultry. However, many species have long been used in traditional medicine. They have been applied for many purposes, ranging from magic charms to removal of corns. [7]
Cotyledon spp. are grown as garden and indoor subjects, practically independent of irrigation in all but full desert conditions, though they cannot survive poor light or bad drainage. Pests that affect them include sucking bugs, members of the suborder Auchenorrhyncha such as the mealy bug ( Pseudococcus ), and similar insects. The inflorescences of the larger species are sometimes used as components of dried arrangements in floral design.
Species include (among others):
The Crassulaceae, also known as the stonecrop family or the orpine family, are a diverse family of dicotyledon flowering plants characterized by succulent leaves and a unique form of photosynthesis, known as Crassulacean acid metabolism (CAM). Flowers generally have five floral parts. Crassulaceae are usually herbaceous but there are some subshrubs, and relatively few treelike or aquatic plants. Crassulaceae are a medium-sized monophyletic family in the core eudicots, among the order Saxifragales, whose diversity has made infrafamilial classification very difficult. The family includes approximately 1,400 species and 34–35 genera, depending on the circumscription of the genus Sedum, and distributed over three subfamilies. Members of the Crassulaceae are found worldwide, but mostly in the Northern Hemisphere and southern Africa, typically in dry and/or cold areas where water may be scarce, although a few are aquatic.
Pachypodium bicolor is a species of plant in the family Apocynaceae.
Pachypodium brevicaule is a species of plant that belongs to the family Apocynaceae.
Adromischus is a genus of flowering plants. They are easily-propagated, leaf succulents from the family Crassulaceae, which are endemic to southern Africa. The name comes from the ancient Greek adros (=thick) and mischos (=stem).
Cotyledon orbiculata, commonly known as pig's ear or round-leafed navel-wort, is a South African succulent plant belonging to the genus Cotyledon.
Tylecodon is a genus of succulent plants in the family Crassulaceae, native to southern Africa.
Kalanchoe pinnata, commonly known as cathedral bells, air plant, life plant, miracle leaf, Goethe plant, and love bush, is a succulent plant native to Madagascar. It is a popular houseplant and has become naturalized in tropical and subtropical areas. The species is distinctive for the profusion of miniature plantlets that form on the margins of its leaves, a trait it has in common with some other members of Bryophyllum.
Dudleya farinosa is a species of succulent plant in the family Crassulaceae known by several common names, including bluff lettuce, powdery liveforever, and powdery dudleya. A coastal plant of northern California and southern Oregon, it is typically found on ocean bluffs just directly above the reach of the waves, and sometimes inland. Its appearance is characterized by lotus-like rosettes of beveled leaves, and in summer the plant erects a tall pink to red peduncle densely covered in bracts, topped with branches of pale yellow flowers. The green or white rosettes of this plant can be seen covering stretches of rocky coast and nearby islets.
Cotyledon tomentosa is a species of flowering plant in the family Crassulaceae, native to South Africa.
Tylecodon buchholzianus is a species of succulent plant in the genus Tylecodon belonging to the family Crassulaceae.
Kalanchoe sexangularis, also known as bushveld kalanchoe, six-angled kalanchoe, or red-leaved kalanchoe, is a species of the succulent genus Kalanchoe, in the family Crassulaceae that is native to Southern Africa.
Dudleya cymosasubsp. cymosa is a species of succulent perennial plant in the family Crassulaceae native to California. It is the autonymous subspecies for Dudleya cymosa, and is known by the common name canyon liveforever. It is native to the California Coast Ranges, the Sierra Nevada and the Santa Monica Mountains. It is characterized by bright-yellow, orange or red flowers and broad, wide leaves. This plant is commonly found growing on rocky outcrops, talus slopes, and in shaded canyons.
Tylecodon wallichii is a species of succulent plant in the genus Tylecodon belonging to the family Crassulaceae. The species is named in honour of Nathaniel Wallich, early 19th century Danish plant hunter, botanist and physician.
Tylecodon reticulatus is a species of succulent plant in the genus Tylecodon belonging to the family Crassulaceae.
Kalanchoideae is one of three subfamilies in the Saxifragales family Crassulaceae, with four succulent genera.
Tylecodon paniculatus, also known as butter bush, butter tree, butterboom or rooisuikerblom (Afrikaans), is a species of succulent plant in the genus Tylecodon belonging to the family Crassulaceae.
Adromischus alstonii is a species of succulent plant from the family Crassulaceae. The species name is the namesake of Edward Garwood Alston, who was a plant enthusiast from Cape Province, South Africa. A. alstonii is endemic to the Succulent Karoo in the Northern Cape, South Africa.
Adromischus bicolor is a perennial, succulent plant in the family Crassulaceae. The species name bicolor refers to the light, grey-green leaves spotted with purple to purple-green spots. It is endemic to the Succulent Karoo of western South Africa, as well as the Eastern Cape, South Africa.
Adromischus filicaulis is a perennial, succulent plant in the family Crassulaceae. It is commonly called brosplakkies in Afrikaans. The species is endemic to South Africa and Namibia.