Genus: Tolumnia

Tolumnia is a genus of epiphytes, lithophytes, and rarely terrestrial orchids, widely distributed over tropical America, from southeast Florida to parts of South America. Similar to other twig epiphytes, the leaves may be cylindric or flattened, often three sided, and arranged in a fan shape with very reduced or absent pseudobulbs. The floral morphology is nearly identical to that found in the genus Oncidium with showy, flat flowers that are relatively large in proportion to the plant, ranging from bright yellow, off-white, pink to purple, often with segments that are spotted. The labellum is lobed, without a nectar cavity and has a prominent callus.

North American Species in this Genus