Medium to large epiphyte. Pseudobulbs oblong, to 18 cm long, compressed. Leaves 1 or 2, strap-like, to 50 cm long, to 4 cm wide. Flowers many, to 3.5 cm wide, mostly yellow with brownish spots and bars; spring. Sepals unequal, laterals narrower than dorsal. Petals larger than sepals, obovate. Labellum 3-lobed, midlobe notched, callus brown.
Ecuador and Peru.
O. ampliatum Lindl. from C and S America is a medium sized epiphyte with long racemes or panicles of many medium sized yellow and brown flowers, each with small clawed sepals and petals and a larger labellum.
O. leucochilum Bateman ex Lindl. from Mexico and C America is a medium to large epiphyte with long panicles of many medium sized mostly green and brown flowers, each with a white labellum with pink or yellow suffusions.
O. sarcodes Lindl. from Brazil is a medium sized epiphyte with long panicles of many medium to large brown and yellow flowers, each with large wavy-edged petals.
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. (as Oncidium excavatum)
