Medium sized terrestrial. Leaves 3?5, elliptic, to 25 cm long, to 5 cm wide, bright green mottled dark green. Flowers solitary or rarely 2, to 10 cm wide; spring. Dorsal sepal elliptic to almost round, larger than laterals, white, greenish at base, with purplish stripes. Petals oblong, narrower than dorsal sepal, drooping, upper margins warty, green, purplish near tip, with dark veins. Labellum helmet-shaped, dark brown, greenish below.

Thailand and Malaysia.

P. barbatum (Rchb. f.) Stein from Malaysia and Thailand is a medium sized terrestrial or epilith with mottled leaves, 1 or 2 white flowers with small purple dots towards base of the segments, dorsal sepal and petals of similar size and shape and a relatively small pouched labellum.

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.