Kalanchoe
Kalanchoe , also written "Kalanchöe" or "Kalanchoë", is a genus of about 125 species of tropical, succulent plants in the stonecrop family Crassulaceae, mainly native to Madagascar and tropical Africa. A "Kalanchoe" species was one of the first plants to be sent into space, sent on a resupply to the Soviet Salyut 1 space station in 1979. Kalanchoes require direct sunlight although they can survive with bright indirect sunlight. They only need to be watered when the soil is completely dry. Description. Most are shrubs or perennial herbaceous plants, but a few are annual or biennial. The largest, "Kalanchoe beharensis  from Madagascar, can reach tall, but most species are less than tall. Kalanchoes open their flowers by growing new cells on the inner surface of the petals to force them outwards, and on the outside of the petals to close them. Kalanchoe flowers are divided into 4 sections with 8 stamens. The petals are fused into a tube, in a similar way to some related genera such as Cotyledon". Taxonomy. The genus "Kalanchoe" was first described by the French botanist Michel Adanson in 1763. The genus Bryophyllum was described by Salisbury in 1806 and the genus Kitchingia was created by  Baker in 1881. "Kitchingia" is now regarded as a synonym for "Kalanchoe", while "Bryophyllum" has also been treated as a separate genus, since species of "Bryophyllum" appear to be nested within Kalanchoe on molecular phylogenetic analysis, "Bryophyllum" is considered as a section of the former, dividing the genus into three sections, "Kitchingia", "Bryophyllum", and "Eukalanchoe". these were formalised as subgenera by Smith and Figueiredo (2018). Etymology. Adanson cited Georg Joseph Kamel (Camellus) as his source for the name. The name came from the Cantonese name 伽藍菜 (Jyutping: gaa laam coi). "Kalanchoe ceratophylla" and "Kalanchoe laciniata" are both called (apparently "Buddhist  monastery "[samghārāma]" herb") in China. In Mandarin Chinese, it does not seem very close in pronunciation ("qiélán cài", but possibly "jiālán cài" or "gālán cài" as the character has multiple pronunciations), but the Cantonese "gālàahm choi" is closer. List of selected species. List of hybrids. Several hybrids within "Kalanchoe" are known: Distribution and ecology. The genus is predominantly native to the Old World. Only one species originates from the Americas. 56 are from southern and eastern Africa and 60 species on the island of Madagascar. It is also found in south-eastern Asia and China. These plants are food plants  for caterpillars of the Red Pierrot butterfly. The butterfly lays its eggs on phylloclades, and after hatching, caterpillars burrow into the phylloclades and eat their inside cells. Cultivation and uses. These plants are cultivated as ornamental houseplants and rock or succulent garden plants. They are popular because of their ease of propagation, low water requirements, and wide variety of flower colors typically borne in clusters well above the phylloclades. The section "Bryophyllum"—formerly an independent genus—contains species such as the "air-plant" "Kalanchoe pinnata". In these plants, new individuals develop vegetatively as plantlets, also known as bulbils or gemmae, at  indentations in phylloclade margins. These young plants eventually drop off and take root. No males have been found of one species of this genus which does flower and produce seeds, and it is commonly called the mother of thousands: "Kalanchoe daigremontiana" is thus an example of asexual reproduction. The cultivars ‘Tessa’ and ‘Wendy’ have gained the Royal Horticultural Society’s Award of Garden Merit. Traditional medicine. In traditional medicine, "Kalanchoe" species have been used to treat ailments such as infections, rheumatism and inflammation. "Kalanchoe" extracts also have immunosuppressive effects. "Kalanchoe pinnata" has been recorded in Trinidad and Tobago as being  used as a traditional treatment for hypertension. A variety of bufadienolide compounds have been isolated from various "Kalanchoe" species. Five different bufadienolides have been isolated from "Kalanchoe daigremontiana". Two of these, daigremontianin and bersaldegenin 1,3,5-orthoacetate, have been shown to have a pronounced sedative effect. They also have the strong positive inotropic effect associated with cardiac glycosides, and with greater doses an increasing effect on the central nervous system. Bufadienolide compounds isolated from "Kalanchoe pinnata" include bryophillin A which showed strong anti-tumor promoting activity, and bersaldegenin-3-acetate and bryophillin C which were less active. Bryophillin C also showed insecticidal  properties.