Etymology - Previously known as Hariota. The present name is a near anagram of the previous name which honoured a 16th century botanist, Thomas Hariot.
The genus name Hatiora was made up by cactus taxonomists Britton and Rose in 1923 to honor an earlier botanist named Thomas Hariot. Previous to this time the genus was more sensibly, Hariota, but due to the guidelines of nomenclature, this previous name had to be rejected.
Today, most authors include 5 or 6 species within the genus. They are all epiphytic, meaning they grow in trees in more wet/humid regions. The stems of these species may be either flat and leaf-like or round in cross section. Some growers prefer to use the genus name Rhipsalidopsis for the species with leaf-like stems. They are similar in that new growth and flowers arise from the end of the existing stem segments only. Flowers range in color from yellow-orange to pink to bright red and the fruits are fleshy round or angled.
In cultivation, hybrids of H. gaertneri and H. rosea are among the most popular of all cactus species in cultivation. They are found world-wide in grocery stores and garden centers. They are often sold as "Spring Cactus" or "Easter Cactus" because they often bloom in spring. Although, if grown properly, these plants will flower 2 or more times within a year. Likewise common, but less-so is the species H. salicornioides which is sold as a hanging basket plant for its quaint stem growth. Other species in the genus are quite uncommon in cultivation.
In the wild, this genus is restricted to Brazil in the southeast of the country.