Said to be derived from the ancient Aztec name.
Epiphytic plants with stems that are cylindrical at the base but flattened above and with wavy edges, widely used in horticulture in hanging baskets. Spines absent except on the new growth. Areoles mostly slightly woolly. Flowers diurnal, funnel-shaped, pink or red; spring. Flower tube narrow, about as long as the flower, scaly and sometimes with bristles in the axils. Fruit spherical to ellipsoid and bearing areoles.
Often grown is N. phyllanthoides (DC.) Britton & Rose from S Mexico (Puebla) which has been widely used for hybridisation. Related to Aporocactus, Disocactus and Heliocereus. Often placed in Discocactus.
Many of the popular hybrids with large and brightly coloured flowers are derived from this genus (often referred to as Phyllocactus or Epiphyllum hybrids or ×Epicactus), although Epiphyllum crenatum (Lindl.) G. Don is also the source of many hybrids. It is believed that N. phyllanthoides (DC.) Britton & Rose was the major parent in extensive hybridisation experiments that occurred in the early 19th century giving rise to a wide range of colours. However, the hybrid mix is now extremely complicated and includes: ×Heliochia (=Heliocereus × Nopalxochia); ×Epixochia (=Epiphyllum × Nopalxochia); ×Heliphyllum (=Heliocereus × Epiphyllum); ×Seleniphyllum (= Heliocereus × Epiphyllum).
More recently the genera Aporocactus and Discocactus have been added to the hybrid mix.
Flowers large, long and narrow-tubed, mostly more than 4 cm wide, diurnal, pink or red (those of Epiphyllum are nocturnal and white).
4 species from S Mexico.
Source: (1997). Cactaceae. In: . Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.
