A genus of approximately 40 species that are epiphytic or lithophytic. Most species occur in the Andes and Caribbean but the genus also occurs in Central America, Mexico and Florida in habitats that range from moist forests to semi-dry, scrub forests. Stems are erect and enclosed by several sheaths with a distinct annulus. There is one leaf per node and the leaves elliptic and leathery. Plants are small and flowers are most often less than 1 cm across. The number of flowers on an inflorescence ranges from one to several that are distichous or secund and sometimes in two opposing ranks. Floral bracts are tubular and the star-like translucent flowers are arranged in rows. Sepals are membranous, ovate, dorsal free or basally connate to lateral sepals. The petals are membranous and the labellum relatively fleshy.