Medium sized epiphyte. Pseudobulbs cylindrical to spindle-shaped, to 15 cm long. Leaves 4-6, strap-like, to 40 cm long, to 3 cm wide. Flowers many, to 4 cm wide, unpleasantly fragrant; autumn to winter. Sepals and petals ovate, upcurved, pointed. Labellum 3-lobed, side lobes pointed, midlobe large and pointed, margins rolled under.

var. maculatum has flowers mostly pale yellowish with reddish-brown spots.

var. unicolor (Hook.) L.O.Williams has flowers that are entirely pale lemon yellow.

Mexico.

M. igneum Lindl. &Paxton from C and S America is medium to large epiphyte with cylindrical, 5-15-leaved pseudobulbs and long racemes of few to many medium sized flowers that are very variable in shape and colour.

Source: Jeanes, J. (2005). Orchidaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.