Courtesy of Tim Hillson








Genus: Cypripedium



Cypripedium , the word, was first used in 1737 by Linnaeus in describing European species. The name Cypripedium originated the word cyprus, where mythological Aphrodite was born. He also used the word pedilum, which meant shoe or slipper, to describe other species. However, Conrad Gesner was the first to describe slipper orchids (Cribb. 1997).

Most all cypripediums are terrestial plants. Most species have a stout and seldom branching rhizome. The rhizome survives the dormant period with the bud of the flower at the terminal position. Most species of cypripedium have three to many leaves growing along the stem. The blades of the leaves are ovate and elliptic in shape. At times they are hairy, especially on the veins and margins (Cribb. 1997).

The inflorescence, the arrangement of flowers and their accessory parts on an axis, are in spicate and racemose form. The number of flowers varies from one to twelve according to the species. The flower contains a triocular ovary which is either stalkless or born on a short stalk. The ovary, at times, can be hairy, glandular, or glabrous. The sepal is the outermost floral envelope , at times the sepal can be fused half their length. The second flora whorl consists of the organs, two petals and a deeply pouched lip. Depending on the species, the petals vary in shape from linear to elliptic and some are hairy on the inner side, and ciliate along the margins (Cribb. 1997).

A distinctive feature of the cypripedium genus is the lip. In this genus, there are five types: the arietinum, calceolus, guttatum, japonicum, and the margaritaceum. Cribb describes the arietinum form as "obliquely obconical with a small subcircular mouth that has an incurved margin and a hairy margin and front" (Cribb 1997). The most common form of the lip is the calceolus form that is "ellipsoidal with incurved side lobes that have a distinct basal crease and an incurved apical margin" (Cribb. 1997). This type of cypripedium species can be found in C. calceolus. The most distinctive form is the guttatum which is unshaped with a slight circular mouth. The margins are incurved with sharp edges around the mouth. The lips of the japonicum type are inflated and elongated. C. acaule exhibits this form of lip. The characteristic of margaritaceum is "dorsiventrically flattened" (Cribb. 1997). The lip of the orchids slipper is used in cross pollination by trapping the insects that are attracted to the flower.

The central part of the flower is compromised of short-stalked columns that arise to the structures of the monocotyled flower. Cribb descrobes the fertile structures as " the stamens are reduced to two lateral anthers and a single terminal sterile one"(Cribb 1997).

Cypripedium species contain seeds that are developed by the fertilization of the ovuale after pollination. The seed takes on a brown color as it matures (Cribb . 1997). All slipper orchids are mostly found in climates that growing occurs during the spring, flowering in the summer and seeding in the fall. Orchids survive by the food stored in their rhizomes. The orchids need a good amount of moisture during their growing season, but too much moisture can rot the stalk (Cribb 1997).





The identification guide is used to define different characteristics of the species within the genus cypripedium. The partial key to the species of cypripedium is stated by Williams in The Field Guide to Orchids of N. America.

1. Margin of lip-pouch opening incurved

Margin of lip-pouch opening not incurved.....................C. guttatum

2. Leaves two, at base of stem; lip-pouch opening longitudinal, narrow...........C. acaule

Leaves two or more, borne on stem; lip-pouch opening oval

3. Leaves two, borne high on stem; flowers clustered ................C. fasciculatum

Leaves two or more, borne along stem

4. Lateral sepal united, at least at base, below lip; lip pouch oval

Lateral sepals free and spreading, not united below lip; lip pouch with conical projection

Below.............................C. arierinum

5. Lip pouch yellow or yellowish; petals long and slender, usually twisted.......C. calceolus

Lip pouch white; petals long and slender, usually twisted.

6. Dorsal sepal about equal to lip in length............C. candidum

Dorsal sepal much longer than lip....................C. montanum

Petals ovate to lanceolate, not twisted, usually same length as or shorter than lip

7. Lip small and white, less than 2 cm. Long

Lip larger, more than 2 cm. Long, pink or (rarely) white..............C. reginae

8. Flowers one or two, borne at top of stem.....................C. passerinum

Flowers three to ten, sometimes more, borne along stem; bracts foliaceous...C. californicum

(Williams. 1983)






Species list: A species list exhibits the scientific names and common names of the species of Cypripedium .



C. acaule

Pink Lady's Slipper & Moccasin Flower

C. artietinum

Ram's Head Lady's slipper

C. bardolphianum



Yellow Lady's Slipper

C. californicum

California Lady's Slipper

C. candidum

Small White Lady's Slipper

C. cordigerum


C. debile


C. dickinsonianum


C. elegans


C. fargesii


C. farreri


C. fasciculatum

Clustered Lady's Slipper

C. fasciolatum


C. flavum


C. formosanum


C. forrestii


C. franchetii


C. guttatum

Spotted Lady's Slipper

C. henryi


C. himalaicum


C. irapeanum


C. japonicum


C. kentickiense


C. lichiangense


C. ludlowii


C. macranthos


C. margaritaceum


C. micranthum


C. molle


C. montanum

Mountain Lady's Slipper

C. palangshanense


C. parviflorum


C. passerinum

Sparrow's Egg Lady's Slipper

C. plectrochilum


C. reginae

Showy Lady's Slipper

C. segawai


C. shanxiense


C. smithii


C. subtropicum


C. tibeticum


C. wardii


C. wumengense


C. yatabeanum


C. yunnanense


( Williams. 1983)



Cypripediums are the showest and most sought after orchid. They are currently being used for medical purposes in North America. The genus cypripedium contains 20-30 species that are distributed in the regions of N. America, Asia, and Europe(Williams. 1983).These cypripedium orchids are great for bog gardens, where they best grow in association with ferns (Griffith, et al. 1995).




Campbell, 1982. The Great Smokey Mountain Wildflowers. The University of Tennessee Press. Tennessee.

Cribb, Phillip. 1997. The Genus CYPRIPEDIUM. Timber Press, Inc. Portland, Oregon

Cronquist, Arthur. 1993. An Integrated System of Classification of Flowering Plants. Columbia University Press. New York.

Griffiths, Mark & Stewart, J. 1995. Manual of Orchids. Macmillan. London. England.

Gupton, O. & Swope, F. C. 1979. The Wildflower of the Shenandoah Valley and Blue Ridge Mountains. University Press of Virginia. Viriginia.

Mabberly, D. J. 1987. The Plant Book. Cambridge University Press. Cambridge. Great Britain.

Williams, Andrew E. & Williams, J. G. 1983. Field Guide to Orchids of N. America. Universe Books. New York. New York.

Wofford, B. E. & Kral, R. 1993. Checklist of the Vascular Plants of Tennessee. BRIT Inc. Fort Worth. Texas.