Genus which is sometimes abbreviated to Angcm in the horticultural trade, it contains over 220 species from dry, tropical woodland environments and thus have characteristic fleshy leaves. foliage tends to vary in shape and structure across species. Most species are epiphytic and thus grow on the surfaces of other organisms and glean nutrition from their immediate surroundings. Some are lithophytes, these plants grow without soil on or in rocks. Flowers are predominantly white, with some tending more towards yellow, orange or green and are considered long lasting. They are produced from unbranched stems called racemes and have 2-lips, which are modified petals called labellum, these have long spur structures at the back.