A long-lived epiphytic cactus from the Atlantic coastal forest of southeastern Brazil, grown indoors almost everywhere for its arching, segmented stems and its showy late-fall and winter flowers in hot pink, magenta, red, orange, salmon, or white. It is the plant most often sold and labeled as a 'Christmas cactus,' but the confusion is near-universal and worth getting right: this is the Thanksgiving, crab, or claw cactus, with sharp, claw-like teeth on the edges of its flat stem segments and a bloom season that runs from late fall into winter. The true Christmas cactus is a different plant, the hybrid Schlumbergera x buckleyi, which has smooth, rounded segment margins and blooms a few weeks later. Unlike a true desert cactus, it is a forest epiphyte that grows on tree branches in dappled light, so it wants bright indirect light, a free-draining mix, sparing water, and — to set its buds — cool nights and short days. A reassuring point that sets it apart from many houseplants: it is non-toxic to cats and dogs.