Schlumbergera microsphaerica

Schlumbergera microsphaerica resembles other species of the genus Schlumbergera in that it has leafless green stems, made up of distinct segments, which act as photosynthetic organs. However, most other species have strongly flattened stems, whereas S. microsphaerica has branching stems made up of narrow, more or less cylinder-shaped segments, each 1.5–4.0 cm (0.6–1.6 in) long by 2–5 mm (0.1–0.2 in) in diameter. Special structures characteristic of cacti, called "areoles", occur in a roughly spiral fashion over the stems. The areoles, which may have bristles, are where the flower buds appear. The flowers usually hang down and are more or less regular (radially symmetrical or actinomorphic). They are described as "fuchsia red" to white in colour and are about 1.5 cm (0.6 in) long. In cultivation in the Northern Hemisphere, plants flower in the spring – March to April. The fruit is green, with up to five not very prominent ribs. The brown seeds have a diameter of about 1 mm (0.04 in).

Schlumbergera microsphaerica occurs only in a small region of the coastal mountains of south-east Brazil, in the states of Rio de Janeiro, Minas Gerais and Espírito Santo, located in the southernmost part of the tropics. Sites where it has been found include Pico das Agulhas Negras in the Itatiaia National Park and the Pico do Cristal and the Pico da Bandeira in the Serra do Caparaó. Plants grow at altitudes of 2,600–2,780 metres (8,530–9,120 ft). Because of their altitude and proximity to the Atlantic Ocean, the coastal mountains have high humidity – warm moist air is forced upwards into higher, colder locations where it condenses. S. microsphaerica usually grows on rocks (epilithic) or on trees (epiphytic). It is listed as threatened by loss of habitat in the IUCN Red List of Threatened Species, but placed in the category of "data deficient", meaning that there is insufficient information to determine its status further. Most plants are now in areas which are legally protected.

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