Spiranthes is a genus of orchids in the subfamily Orchidoideae. They are known commonly as ladies tresses, ladies'-tresses, or lady's tresses. The genus is distributed in the Americas, Eurasia, and Australia. The genus name Spiranthes is derived from the Greek speira ("coil") and anthos ("flower"), and was inspired by the spirally arranged inflorescence.
Spiranthes romanzoffiana, commonly known as hooded lady's tresses or Irish lady's-tresses, is a species of orchid. Collected by Chamisso during the Romanzov expedition it was described by him in 1828 and named for Count Nikolay Rumyantsev who financed the expedition. This orchid is native to North America, Ireland and the British Isles.
Spiranthes ochroleuca, commonly called the yellow nodding lady's tresses, is a species of orchid occurring from southeastern Canada to the eastern United States.
Spiranthes porrifolia is a species of orchid known by the common names creamy lady's tresses and western ladies' tresses. It is native to the western United States from Washington and Idaho to southern California. It can be found in moist habitats, such as mountain meadows, swamps, fens, and riverbanks. It is a perennial herb growing from a tuberous root system, reaching a maximum height around 60 cm (24 in). The leaves are mainly located around the base of the erect stem. They are linear or lance-shaped, or sometimes nearly oval. The top of the stem is occupied by the inflorescence, a dense spiral of many flowers. Each flower is somewhat tubular, with an upper and lower lip, and cream to yellowish in color.
Spiranthes diluvialis is a rare species of orchid known as Ute lady's tresses. The species name diluvialis means "of the flood". It is native to the western United States, where there are scattered, mostly small occurrences in the states of Colorado, Idaho, Montana, Nebraska, Nevada, Utah, Washington, and Wyoming. An occurrence was recently discovered in southern British Columbia. The plant faces a number of threats to its existence. It is a federally listed threatened species of the United States.
Spiranthes infernalis, common name Ash Meadows lady's tresses, is a rare species of orchid known from only four locations in Nevada, all close to one another. The type locale is inside Ash Meadows National Wildlife Refuge, in Nye County approximately 90 miles (140 km) WNW of Las Vegas. The site is a seasonally wet meadow.
Spiranthes odorata, marsh lady's tresses or common lady's tresses, is a species of flowering plant in the orchid family, native to the southeastern United States, from Texas eastwards and northwards to Delaware. It grows in moist, partially shaded environments with acidic or neutral soil.
Spiranthes ovalis, commonly called the October lady's tresses, is a species of orchid that is native to eastern North America.
Spiranthes australis, commonly known as austral ladies tresses, is a species of orchid that grows from southern Caspian Sea and Himalayan Mountains to the South-West Pacific and north throughout Japan. It has up to about ten leaves at the base of a flowering stem with up to sixty small pink and white flowers spirally arranged around it.
Spiranthes lucida, the shining ladies'-tresses, is a species of orchid native to northeastern North America.
Spiranthes incurva, the Sphinx ladies' tresses, is a species of flowering plant in the family Orchidaceae. This orchid is native to the upper Midwest and Great Lakes Basin of North America. The species was originally described as Ibidium incurvumJenn. in 1906. Long treated as part of a sensu latoSpiranthes cernua, the species complex was reevaluated and Spiranthes incurva reestablished as a separate species in 2017. Spiranthes incurva is an ancient natural hybrid of S. cernuasensu stricto and S. magnicamporum.
Spiranthes arcisepala, the Appalachian ladies' tresses, is a species of flowering plant in the family Orchidaceae. This orchid is native to eastern North America. Long treated as part of Spiranthes cernua the species complex was reevaluated and Spiranthes arcisepala established as a separate species in 2017.
Spiranthes niklasii, Niklas' ladies' tresses, is a terrestrial orchid nearly endemic to the Ouachita Mountains in Arkansas and Oklahoma with a few other known populations.
Spiranthes perexilis, the languid ladies’-tresses, is a species of orchid native to California and Oregon.
Spiranthes triloba, the panther ladies' tresses is a terrestrial orchid endemic to Florida.
Spiranthes bightensis, the Atlantic ladies tresses, is a terrestrial orchid native to coasts of the north-eastern United States.
Spiranthes casei, or Case's lady's tresses, is a species of orchid native to the northeastern United States and Canada.
Spiranthes igniorchis, or fire ladies' tresses, is a species of orchid endemic to Florida.
Spiranthes sheviakii, the old field ladies' tresses, is a species of orchid growing in North America.
