Prasophyllum, commonly known as leek orchids, is a genus of about 140 species of flowering plants in the orchid family, Orchidaceae and is found in Australia and New Zealand. The Australian species are found in all states but have not been recorded in the Northern Territory. The common name arises from their having a hollow, leek- or onion-like leaf. Some species only flower after summer fires and have flowers similar to those of Xanthorrhoea which flower at the same time, suggesting that they employ the same pollinating insects. Leek orchids are similar to those in the genus Genoplesium except that the free part of the leaf is cylindrical and the labellum has a solid connection to the column. They range in size from the little laughing leek orchid at about 15 cm (6 in) to the king leek orchid which grows up to 2 m (80 in) tall.
Cyrtostylis reniformis, commonly known as common gnat-orchid, is a species of orchid endemic to eastern Australia. It usually has a single kidney-shaped leaf and a flowering spike with up to eight reddish flowers with a shelf-like labellum.
Genoplesium fimbriatum, commonly known as the fringed midge orchid is a small terrestrial orchid found from southern Queensland to southern New South Wales. It has a single thin leaf and up to thirty green to brownish-green flowers with red stripes and a red-tipped labellum with hairy edges.
Prasophyllum alpinum, commonly known as the alpine leek orchid, is a species of orchid endemic to Tasmania. It was formerly described as occurring in mainland Australia but has smaller flowers than the species occurring there. It has a single, tube-shaped leaf and up to fourteen green to greenish-brown flowers and grows in subalpine areas.
Pterostylis revoluta, commonly known as the autumn greenhood, is a species of orchid endemic to south-eastern Australia. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering spike. This greenhood has white and green flowers that have a long, curved, pointed labellum which extends beyond the sinus between the lateral sepals.
Microtis media subsp. media, commonly known as the common mignonette orchid, is a species of orchid which is endemic to the south–west of Western Australia. It is a common, widespread orchid with a single smooth, tubular leaf and a flowering spike with up to one hundred small green flowers. It differs from Microtis media subsp. densiflora in the shape of its flower spike and the shape of its labellum.
Prasophyllum australe, commonly known as the southern leek orchid or austral leek orchid, is a species of orchid and is endemic to south-eastern Australia. It has a single tubular, green leaf and up to fifty scented, greenish-brown flowers with red stripes.
Prasophyllum flavum, commonly known as the yellow leek orchid, is a species of orchid endemic to eastern Australia. It has a single tubular, green leaf with only a short free section and up to fifty scented, yellowish-green flowers.
Prasophyllum cucullatum, commonly known as the hooded leek orchid, is a species of orchid endemic to the south-west of Western Australia. It is a tall orchid with a single smooth, tubular leaf and up to fifty or more purplish-red and white flowers with a frilled labellum crowded along a relatively short flowering stem.
Prasophyllum fuscum, commonly known as the slaty leek orchid or tawny leek orchid, is a species of orchid endemic to a small region of New South Wales. It has a single tubular green leaf and up to thirty greenish brown to reddish brown flowers. There is debate about the taxonomy of the species with some authorities considering Prasophyllum uroglossum as a separate species. Only about twenty five plants are known to survive in south-western Sydney.
Prasophyllum macrostachyum, commonly known as the laughing leek orchid, is a species of orchid endemic to the south-west of Western Australia. It has a single smooth, tube-shaped leaf and up to thirty yellowish-green and purple flowers. It is one of the few Western Australian leek orchids which is not stimulated by summer fires and also has an unusually long flowering period.
Prasophyllum patens, commonly known as the broad-lipped leek orchid or sandstone leek orchid, is a species of orchid endemic to the Sydney region of New South Wales. It has a single tubular green leaf and up to thirty green to greenish-brown, lemon-scented flowers with a white labellum.
Prasophyllum striatum, commonly known as the streaked leek orchid, is a species of orchid endemic to New South Wales. It has a single thin, tube-shaped leaf and up to ten greenish and whitish flowers with reddish or purplish stripes. It differs from other leek orchids in having a very thin leaf and prominently streaked flowers.
Genoplesium rufum, commonly known as the rufous midge-orchid, is a species of orchid endemic to New South Wales. It has a single thin, wiry leaf and up to twenty five drooping, pinkish or reddish flowers on a flowering stem which is fused to the lower part of the leaf. It was formerly thought to range from Queensland to South Australia and Tasmania but specimens in other states are now assigned to Genoplesium clivicola.
Corunastylis nigricans, commonly known as the Kangaroo Island midge orchid is a small terrestrial orchid endemic to South Australia. It has a single thin leaf and up to twenty five purplish brown flowers with a shiny, hairless, dark purplish labellum. It is sometimes confused with Genoplesium nigricans which has differently coloured flowers and a much wider distribution. It is regarded as a synonym of G. nigricans by the World Checklist of Selected Plant Families.
Genoplesium baueri, commonly known as the brittle midge orchid, is a small terrestrial orchid which is endemic to New South Wales. It has a single thin leaf and up to nine yellowish green to reddish brown flowers. It is mostly only found in coastal and near-coastal heath and woodland between Port Stephens and Ulladulla.
Microtis alba, commonly known as the white mignonette orchid or slender onion-orchid, is a species of orchid endemic to the south-west of Western Australia. It has a single hollow, onion-like leaf and up to sixty small, green and white flowers with a strong musky fragrance. It is much more common after a fire the previous summer than in unburned country.
Microtis pulchella, commonly known as the beautiful mignonette orchid or beautiful onion orchid, is a species of orchid endemic to the south-west of Western Australia. It has a single hollow, onion-like leaf and up to twenty five white, thinly textured flowers with a slight perfume. It only flowers after fire and only sometimes produces short, thread-like leaves in the absence of fire.
Diuris setacea, commonly called the bristly donkey orchid, is a species of orchid that is endemic to the south-west of Western Australia. It has a tuft of up to ten twisted leaves at its base and up to seven yellow flowers with a few brown markings. It grows in moist soil on granite outcrops and flowers much more prolifically after fire the previous summer.
Cryptostylis ovata, commonly known as slipper orchid or western tongue orchid, is an orchid endemic to Western Australia. It is a common, summer flowering species with dark green leaves with a white central vein and up to fifteen pale greenish flowers with a brownish red labellum with a network of darker veins.
