Robust epiphyte. Stem short. Leaves elliptic, to 45 cm long, to 11 cm wide, fleshy, dark green. Inflorescences to 1 m long. Flowers usually many, to 7.5 cm wide, fragrant, mostly white to pale purplish; mostly winter to spring. Sepals ovate to elliptic. Petals rhombic, clawed. Labellum 3-lobed, side lobes spreading, midlobe almost round with an anchor-shaped terminal appendage, base yellow with reddish-brown spots.

Philippines.

P. stuartiana Rchb. f. from the Philippines is a robust epiphyte with racemes of many, mainly white flowers that have reddish-brown spots on the labellum and base of the lateral sepals.

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.