M. pygmaeum has two small leaves and well separated pseudobulbs. This plant has some pseudobulbs with four leaves and pseudobulbs not well separated. The flowers on M. pygmaeum are smaller and form a narrow tube compared to other species; these flowers are not tubelike as shown in the illustratons. This plant closely matches the photo of M. decoratum in the Kew's POWO. Images on the Orchids of New Guinea website shows M. pygmaeum to be a smaller plant with widely spaced bifoliate pseudobulbs and leaves held opposite each other, unlike this plant. The flower size of this plant is also a match to M. decoratum.