''Spiranthes incurva'', the Sphinx ladies' tresses, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the family

Orchidaceae Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

. This orchid is native to the

upper Midwest The Upper Midwest is a region in the northern portion of the U.S. Census Bureau's Midwestern United States. It is largely a sub-region of the Midwest. Although the exact boundaries are not uniformly agreed-upon, the region is defined as referring ...

and Great Lakes Basin of North America. The species was originally described as ''Ibidium incurvum'' in 1906. Long treated as part of a ''sensu lato'' ''

Spiranthes cernua ''Spiranthes cernua'', commonly called nodding lady's tresses, or nodding ladies' tresses, is a species of orchid occurring from Maritime Canada to the eastern and southern United States. As the common name suggests ''cernua'' means "nodding", or ...

'', the species complex was reevaluated and ''Spiranthes incurva'' reestablished as a separate species in 2017. ''Spiranthes incurva'' is an ancient natural

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two dif ...

of ''S. cernua'' ''sensu stricto'' and '' S. magnicamporum''.

References

incurva Orchids of the United States Plants described in 1906 {{Orchidoideae-stub