The name of this genus is derived from the Greek words acanthos ("spiny") and ephippion ("saddle"), referring to the saddle-like labellum of the plants.

This terrestrial and sometimes myco-heterotrophic genus of sympodial orchids is distributed from the Indian subcontinent to Taiwan, China, Japan, Southeast Asia, New Guinea and the southwest Pacific.

[4] The erect inflorescence arises laterally from the pseudobulbs, with 3 to 6 flowers, subtended by large, glabrous bracts.

The flowers are prominent, large, striated cup- or urn-shaped, fleshy, waxy, and about 4 cm long.

The flowers have a wide range of colors, from dull yellow to red to shades of orange and pink, marked with stripes or spots.