Calypso bulbosa

(Linnaeus) Oakes

in Z. Thompson, Nat. Hist. Vermont 1: 200. 1842.

Basionym: Cypripedium bulbosum Linnaeus Sp. Pl. 2: 951. 1753
Synonyms: Cytherea bulbosa (Linnaeus) House
Treatment appears in FNA Volume 26. Treatment on page 623.

Plants 4.5–22 cm. Leaves: blade elliptic to suborbiculate or ovate, often cordate, 10–65 × 12–52 mm. Inflorescences: floral bracts lance-acuminate, 5–28 mm. Flowers pink, magenta, or rarely white; sepals and petals erect-spreading, linear-lanceolate to linear-oblong, 10–24 × 1.5–5 mm; lip 13–23 × 4–13 mm, lamina shorter than to longer than apical horns, basal bristles sparse to extensive, brightly and contrastingly colored to dull and obscure. Capsules erect, ellipsoid to lanceoloid, 2–3 × 1–1.5 cm. 2n = 28 [var. bulbosa].


V26 1273-distribution-map.jpg

Circumpolar, North America, Europe, Asia (China, Japan, Russia).


Varieties 3 (2 in the flora).

Selected References



1 Bristles of lip yellow, extensive; lamina white or suffused with pink, usually equaling or longer than horns. Calypso bulbosa var. americana
1 Bristles of lip whitish or color of lamina, sparse; lamina commonly with reddish markings on dull white, usually shorter than horns. Calypso bulbosa var. occidentalis