Ladys Slipper, Cypripedium reginae
Lady Slippers describes the orchids in the subfamily Cypripedioidea, which includes the genera Cypripedium, Mexipedium, Paphiopedilum, Phragmipedium and Selenipedium. They are distinguished by their slipper-shaped pouches (modified labellums), which function by trapping insects so that they are forced to climb up past the staminode, behind which they collect or deposit pollinia.
This subfamily has been considered by some (Rasmussen, 1985) to be a family Cypripediaceae, separate from the Orchidaceae.
The subfamily Cypripedioideae is a monophyletic clade and consists of five genera. Their common features are two fertile diandrous (= with two perfect stamens) anthers, a shield-shaped staminode and a saccate (sac-shaped) lip.
Cypripedium are found across much of North America, as well as in parts of Europe. The state flower of Minnesota is the Showy Lady’s Slipper (Cypripedium reginae).
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, over-collecting 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.