Cypripedium passerinum 

 Sparrow's Egg Lady's Slipper 



A. Classification 



1. Family: Orchidaceae (Orchid Family). The Orchid Family is perhaps the largest family 

 of vascular plants, with over 15,000 species worldwide (Cronquist 1988). Most of these 

 species are in the tropics. Sometimes the genus Cypripedium is segregated from the 

 orchid family and placed in the Cypripediaceae (Weber and Wittmann 1992). 



2. Genus: Cypripedium . the lady's slippers, is a genus of about 50 species native to North 

 America and Eurasia (Correll 1950). 



3. Species: Cypripedium passerinum Richards 



B. Present legal or other formal status 



1. Federal status 



a. U.S. Fish and Wildlife Service: none 



b. U.S. Forest Service: Sensitive in Region 1 (U.S. Forest Service 1994). 



2. State: The Montana Natural Heritage Program ranks the species G4G5 and S2 (Heidel 

 1995). This signifies that it is apparently to demonstrably secure throughout it's global 

 range but is imperilled because of rarity in Montana. 



C. Description 



1. General nontechnical description: Sparrow's egg lady's slipper has leafy stems up to 35 

 cm high from slender, creeping rhizomes. The 3-5 broadly lance-shaped leaves are up to 

 35 cm long and clasp the stem. The herbage is covered with long, soft hairs and is 

 usually somewhat sticky. The one or two flowers are subtended by a leafy bract which is 

 longer than the inflorescence. The sepals are green and 10-16 mm long, the upper one 

 longer than the lower two. The petals are white, the lower one is pouchlike with purple 

 spots on the inside, and the other two resemble the sepals but are shorter. The erect 

 capsule is ovoid and bears thousands of tiny seeds (U.S. Forest Service 1995). Slides of 

 flowering plants photographed on the KNF are included in Appendix C. 



2. Technical description: Plant terrestrial, pubescent, up to 35 cm tall from a short 

 rhizome with fibrous roots. Leaves 3-5, ovate-lanceolate, plicate, light green, 5-15 X 1.5- 

 5 cm, sheathing the stem. Inflorescence with a usually solitary, inconspicuous flower. 

 Floral bract foliaceous, ovate-lanceolate, 3-5 X 1-2 cm, sheathing the ovary. Ovary 

 subsessile, stout, pubescent, 17X7 mm. Dorsal sepal suborbicular, concave, yellow 

 green, 1.5-2 X 1-1.5 cm. Lateral sepals united nearly to apex and concave behind the lip, 

 or sometimes free; similar to the dorsal sepal. Petals linear-oblong, spreading, flat, white, 

 12-20 X 3-4 mm. Lip an obovoid sac, the margins of the orifice folded in, white, 

 suffused with pink near the base, minutely spotted with purple at the orifice and on the 

 inside, 12-20 X 8-13 mm. Staminode ovate, white with yellow apex and spotted with 

 purple, 6X5 mm. Capsule ellipsoid, 1.5 X 2.5 cm. (Luer 1975) 



3. Local field characters: Unlike other lady's slippers on the KNF. Cypripedium 

 passerinum has inconspicuous flowers which are whiteish green and do not have showy 



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