Description and Distribution of Cypripedium
Cypripedium was first used to describe the slipper orchids by Linnaeus in 1737. The name is derived from the island of Cypris, the birthplace of Aphrodite (Venus), and pedilum which refers to shoe or slipper. Thus, common names include Venus' Slipper and Lady's Slipper. In Linnaeus' time into the 20th century, the genus Cypripedium included all the slipper orchids.
Map was drawn from a digital map from www.planiglobe.com. ©planiglobe 2004
Distribution of Cypripedium is confined to the northern temperate regions.
Today, the roughly 150 species of slipper orchids are all contained within the subfamily Cypripedioideae. The slippers have been divided into five genera. Cypripedium includes all of the temperate deciduous terrestrial orchids with plicate leaves and persistent perianth. Paphiopedilum contains Asiatic orchids with hard leaves, Phragmipedium contains South American species, Selenipedium is a primitive genus of South American species, and Mexipedium contains a single species related to Phragmipedium.
The genus Cypripedium contains about 45 species of northern temperate terrestrial orchids. Today, about 30 species occur in China and 14 in North America. The western part of Europe has only a single species. Since more primitive relict forms of slipper orchids (Mexipedium, Selenipedium) exist in Meso America and North America it is thought that slipper orchids originated in the northern continental mass. Evidence suggests that evolution in Cypripedium has occurred from tall stems with many leaves and flowers to shorter stems with a single leaf and single flower.
Cypripedium is divided into ten sections; in section Subtropica the plants are tall with many flowers that are similar to the flowers of Selenipedium. In section Trigonopedia, plants have evolved to having essentially no aerial stem and a single leaf and flower.
