Cypripedioideae

Lady Slipper orchid
An orchid of the genus Paphiopedilum
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Asparagales
Family:	Orchidaceae
Subfamily:	Cypripedioideae
Genera
See Taxonomy of the orchid family.

Lady's slipper orchids, lady slipper orchids or slipper orchids are the orchids in the subfamily Cypripedioidea, which includes the genera Cypripedium, Mexipedium, Paphiopedilum, Phragmipedium and Selenipedium.^[1] They are characterised by the slipper-shaped pouches (modified labellums) of the flowers – the pouch traps insects so they are forced to climb up past the staminode, behind which they collect or deposit pollinia, thus fertilizing the flower.

This subfamily has been considered by some to be a family Cypripediaceae, separate from the Orchidaceae.^[2]

Lady's slipper orchid (Cypripedium calceolus)

The subfamily Cypripedioideae is monophyletic and consists of five genera. Their common features are two fertile diandrous (that is, with two perfect stamens) anthers, a shield-shaped staminode and a saccate (sac-shaped) lip.

The Cypripedium genus is found across much of North America, as well as in parts of Europe and Asia. The state flower of Minnesota is the Showy Lady's Slipper (Cypripedium reginae). The Lady's Slipper is also the official provincial flower of Prince Edward Island, a province of Canada.

Paphiopedilums are found in the tropical forests of southeast Asia reaching as far north as southern China. Paphiopedilum is quite easy to cultivate and therefore is popular among orchid enthusiasts. In fact, overcollecting of this genus has caused some problems in its original habitat.

Phragmipedium, found across northern South and Central America, is also easy to cultivate as it requires lower temperatures than Paphiopedilum, eliminating the need for a greenhouse in many areas.

The lady's slipper is also known in the United States of America as the moccasin flower, from its resemblance to a shoe or moccasin.

Gallery

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  A yellow lady slipper from Percé, Quebec

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  Pink Lady's Slipper, found in Bristol, Vermont (Cypripedium acaule)

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  Spotted Lady's Slipper (Cypripedium guttatum) in Alaska Peninsula National Wildlife Refuge

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  pink Lady's Slipper, found in Maine (USA) on Mt. Agamenticus

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  Lady slipper found in Lupton, MI at the Rifle River State Recreation Area

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  Lady slipper found along the Jordan River Pathway, East Jordan, Michigan

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  Lady slipper found along the Jordan River Pathway, East Jordan, Michigan

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  Pink Lady's Slippers in Exeter, NH. (photo taken at night with a light)

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  Pink Lady Slippers, found in Rhode Island (Cypripedium acaule)

References

1. ^ Cash, C. (1991). The Slipper Orchids. Timber Press. ISBN 0-88192-183-1. 
2. ^ Rasmussen, F. N. 1985. "Orchids". In R. M. Dahlgren, H. T. Clifford, and P. F. Yeo [eds.], The families of the monocotyledons. Springer Verlag, Berlin.

Further reading

• Cox, A.V., A. M. Pridgeon, V. A. Albert, and M. W. Chase. 1997. Phylogenetics of the slipper orchids (Cypripedioideae: Orchidaceae): nuclear rDNA ITS sequences. Plant Systematics and Evolution 208: 197-223. PDF
• Pridgeon, A.M.; Cribb, P.J.; Chase, M.W. & F. N. Rasmussen (1999): Genera Orchidacearum Vol. 1, Oxford U. Press. ISBN 0-19-850513-2

External links

• The Slipper Orchid Alliance
• SlipperOrchids.info
• United Plant Savers "At Risk Plants List"