After J. Ross who collected orchids in Mexico in the 1830s, and partly derived from Odontoglossum which these species resemble.
Epiphytic herbs, sympodial, with short creeping rhizomes. Stems thickened into ovoid to spherical pseudobulbs, compressed, furrowed with age, subtended by sheaths. Leaves apical, usually 2, short and broad, leathery, stalked. Inflorescences basal racemes, erect to arching. Flowers resupinate, usually few, large, showy, usually yellow with brown markings. Sepals similar, free. Petals similar to sepals or wider, free. Labellum entire or 3-lobed, free, lateral lobes small, midlobe large with a prominent callus. Column long, winged near tip. Pollinia 2, pear-shaped.
About 4 species from Mexico and C America.
The large yellowish flowers with prominent brownish suffusions; differs from Odontoglossum by the free labellum with small ear-like basal lobes and prominent callus.
Source: (2005). Orchidaceae. In: . Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.