The genus Hoya is found in South East Asia through Australia. They are adaptable plants found everywhere from true rain forests through the slopes of the Himalayas, from semi-arid niches in Australia to damp forests. They range from vines, the most common form, to shrub-like growth. Most are epiphytic. Hoyas are in the family commonly known as milkweeds. They are most closely related to Stapelia, Ceropegia and Dischidia. They were first identified as a new genus by Robert Brown in 1802. There are now several hundred distinct species. Many of these species are in cultivation. However, the exact identification of many of these species is not always correct. All the hobbyist can do is maintain the identification that came with the plant and try to verify identity through photographs and descriptions.