Small epiphyte. Stems to 1 cm long. Leaves obovate to oblanceolate, to 7 cm long, to 1 cm wide, leathery, green above, purplish below. Inflorescences to 15 cm long, zig-zagged, erect. Flowers 4-12, to 1.2 cm long, green, white or yellowish with purple stripes; spring to summer. Dorsal sepal free. Lateral sepals joined for most of their length, slightly longer than dorsal. Petals much smaller than sepals. Labellum entire, small, oblong.

Mexico to Brazil and West Indies.

P. tribuloides (Sw.) Lindl. from C America and the West Indies is a small epiphyte with very short stems, small leaves and 1-3 small red flowers in short fascicles.

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.