Platanthera L. C. Rich.
The Rein orchids, bog orchids, fringed orchids
Platanthera leucophaea, the Eastern prairie-fringed orchid
The name Platanthera is derived from the Greek terms meaning
"wide anther", and refers to the characteristic Richard felt distinguished
Platanthera from Orchis and Habenaria. However, the
primary characteristics that distinguish Platanthera from these two
genera are the absence of stigmatic processes and ovoid root-tuberoids.
As currently defined, the genus contains about 85 species, distributed throughout
the temperate and boreal regions. Particular centers of diversity are found
in eastern Asia and the southeastern United States. Wisconsin is home to
10 species. This genus is the subject of my dissertation research. I am
investigating molecular evolution and adaptive radiation of Platanthera,
particularly as it relates to pollination biology. To find out more about
my research, and see a preliminary molecular phylogeny of the genus, click
here.
A. Leaves basal
B. 2 Leaves
- Scape bearing one to several bracts; lip linear, obtuse...orbiculata
- Scape lacking bracts; lip lanceolate, acuminate or acute, "hooked"
in appearance...hookeri
BB. Leaf solitary...obtusata
AA. Leaves cauline
C. Lip fringed or dissected, three-lobed
- Flowers purple (rarely white)...psycodes
- Flowers white, fragrant, spur much longer than the ovary; plant of
moist prairies...leucophaea
- Flowers green or greenish-white; lip heavily dissected; spur equal
to, or only slightly longer than, ovary...lacera
CC. Lip entire, acute, acuminate or obtuse
D. Lip acute or acuminate
- Flowers typically white, fragrant; base of lip dilated...dilatata
- Flowers typically green, not fragrant; base of lip not dilated...hyperborea
DD. Lip obtuse, slightly three-lobed
- Lip bearing a basal tubercle, leaves several...flava
var. herbiola
- Lip lacking tubercle, leaf appearing solitary (others reduced and
bract-like)...clavellata
Go to the list of the species of Platanthera.
Return to the main LIST of the Orchids of
Wisconsin.
Return to the main KEY to the Orchids of
Wisconsin.