Caladenia graminifolia, commonly known as the grass-leafed spider orchid is a species of orchid endemic to the south-west of Western Australia. It has a single glabrous leaf and one or two short-lived, greenish-yellow and red flowers which have a narrow labellum with long teeth on its sides. Description Caladenia graminifolia is a terrestrial, perennial, deciduous, herb with an underground tuber and a single, nearly hairless leaf, long and about wide. One or two greenish-yellow and red flowers long and wide are borne on a stalk tall. The flowers are self-pollinating and are only open for a day or two. The lateral sepals and petals have thickened glandular tips, more prominent on the lateral sepals. The dorsal sepal is erect, long and wide. The lateral sepals are long and wide, turn downwards and often cross each other. The petals are long and about wide and spread widely, mostly horizontally. The labellum is long and wide and greenis-white with a red tip. The sides of the labellum have a fringe of teeth up to long and there are two or four rows of maroon calli up to long, along the centre of the labellum. Flowering occurs from August to September. Taxonomy and naming Caladenia graminifolia was first formally described by Alex George in 1971 and the description was published in Nuytsia from a specimen at Culham Inlet. The specific epithet (graminifolia) is derived from the Latin gramen, graminis meaning "grass" and -folius meaning "-leaved", referring to the grass-like leaf of this orchid. Distribution and habitat The grass-leafed spider orchid occurs between Mount Manypeaks and Israelite Bay in the Esperance Plains and Mallee biogeographic regions. It grows in woodland under tall shrubs and sometimes on granite outcrops. Conservation Caladenia graminifolia is classified as "Not Threatened" by the Western Australian Government Department of Parks and Wildlife. References graminifolia Orchids of Western Australia Endemic orchids of Australia Plants described in 1971 Endemic flora of Western Australia