This is Schlumbergera, commonly called Christmas Cactus, because it flowers in winter. What is it called in southeast Brazil, where it occurs in the wild?
Flor de Natal (Christmas flower)
3939
Flor de Dezembro (December flower)
3506
Flor de Maio (May flower)
4087
Flor de Papai Noel (Father Christmas Flower)
2368
In Brazil, the genus is referred to as Flor de Maio (May flower), reflecting the period in which they flower in the Southern hemisphere.