Spiranthes cernua, commonly called the nodding lady's 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 "bowed" in Latin.
|Nodding lady's tresses|
Spiranthes cernua has long been described as a species complex, exhibiting different morphologies throughout its range. Charles Sheviak, now retired curator of the New York State Museum Herbarium, explored this diversity in great detail, eventually describing Spiranthes magnicamporum to represent large, later-flowering individuals with tuberous roots from the Midwest . More recently, molecular and morphological work has recognized additional cryptic species in need of description; these newly recognized species are sometimes not closely related to S. cernua.
Broadly, the Spiranthes cernua species complex includes:
- Spiranthes arcisepala (Appalachian Mountains and eastern Great Lakes Basin)
- Spiranthes cernua sensu stricto
- Spiranthes incurva (ancient hybrid between S. cernua s.s. and S. magnicamporum, Great Lakes Basin, northern Ohio River Valley, and Great Plains)
- Spiranthes magnicamporum (Great Plains ladies's tresses)
- Spiranthes niklasii (ancient hybrid between S. cernua and S. ovalis, Ouachita Mountains and Crowley's Ridge, Arkansas)
- Spiranthes ochroleuca (Appalachian Mountains and eastern Great Lakes Basin)
- Spiranthes ×kapnosperia (hybrid between S. cernua and S. ochroleuca, Great Smoky Mountains region)
A commonly cultivated variety is Spiranthes cernua 'Chadds Ford', grown because of its larger flowers, ease of cultivation, and other merits.
This species blooms in the autumn, and is commonly found along roadsides and pond edges.
- "Spiranthes cernua". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 27 November 2015.
- Sheviak, Charles (1982). "Biosystematic study of the Spiranthes cernua complex". Bulletin of the New York State Museum Science Service. 448 – via Google Scholar.
- Sheviak, Charles J. (1973). "A New Spiranthes from the Grasslands of Central North America". Botanical Museum Leaflets, Harvard University. 23 (7): 285–297. ISSN 0006-8098. JSTOR 41762281.
- Pace, Matthew C.; Cameron, Kenneth M. (2017). "The Systematics of the Spiranthes cernua Species Complex (Orchidaceae): Untangling the Gordian Knot". Systematic Botany. 42 (4): 640–669. doi:10.1600/036364417x696537.
|This Orchidoideae-related article is a stub. You can help Wikipedia by expanding it.|