What is "schlumbergera"

n. (context botany English) Any member of the cactus genus ''Schlumbergera''.

Schlumbergera is a small genus of cacti with six species found in the coastal mountains of south-eastern Brazil. Plants grow on trees or rocks in habitats that are generally shady with high humidity, and can be quite different in appearance from their desert-dwelling cousins. Most species of Schlumbergera have stems which resemble leaf-like pads joined one to the other and flowers which appear from areoles at the joints and tips of the stems. Two species have cylindrical stems more similar to other cacti. In Brazil, the genus is referred to as (May flower), reflecting the period in which they flower in the Southern Hemisphere.

This genus contains the popular house plants known by a variety of names including Christmas Cactus, Thanksgiving Cactus, Crab Cactus and Holiday Cactus, which are Schlumbergera cultivars, and flower in white, pink, yellow, orange, red or purple. (The Easter Cactus or Whitsun Cactus, which may also be called a Holiday Cactus and has vivid scarlet flowers in the most commonly grown form, is now placed in the genus Hatiora.) The cultivars of Schlumbergera fall into two main groups:

• The Truncata Group contains all cultivars with features derived mainly from the species S. truncata: stem segments with pointed teeth; flowers held more or less horizontally, usually above the horizontal, whose upper side is differently shaped from the lower side (zygomorphic); and pollen which is yellow. They generally flower earlier than members of the Buckleyi Group and although common names are not applied consistently may be distinguished as Thanksgiving Cactus, Crab Cactus or Claw Cactus.
• The Buckleyi Group contains all cultivars with at least some features clearly showing inheritance from S. russelliana: stem segments with rounded, more symmetrical teeth; more or less symmetrical (regular) flowers which hang down, below the horizontal; and pollen which is pink. They generally flower later than members of the Truncata Group and are more likely to be called Christmas Cactus.