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Pterostylis (family Orchidaceae) A genus of terrestrial orchids which have thin, soft, fleshy leaves held in a radical rosette. The plants produce 1 or more underground tubers. The flowers are green, white, or brownish, and either solitary or held in a terminal raceme. The middle sepal and upper 2 petals form a hood. The 2 lower sepals form a lower lip and are often extended into long, thin tails. The lower lip is either incurved or reflexed. The labellum is usually narrow. The fruit is a 3-celled capsule containing numerous fine seeds. There are about 60 species in the western Pacific region, nearly all endemic (see ENDEMISM) to Australia. Many species are cultivated as ornamentals.