quinquelobata Poir. = Spiranthes torta (Thunb.) Garay & Sweet 
spiralis L. = Spiranthes spiralis (L.) Chevall. 
torta Thunb. = Spiranthes torta (Thunb.) Garay & Sweet 
unilateralis Poir. = Brachystele unilateralis (Poir.) Schltr. 
Orchiastrum Seguier 
porrifolium (Lindl.) Greene = Spiranthes porrifolia Lindl. 
Romanzoffianum (Cham.) Greene = Spiranthes Romanzoffiana Cham. 
Orchis L. 
ventricosa (Vell.) Steud. = Sarcoglottis ventricosa (Vell.) Hoehne 
Pelexia Poit. ex Lindl. in Bot. Reg. 12: sub t. 985, 1826, nom. 
CONS. 
Etymology: Pe/ex = helmet, in reference to the appearance 
of the dorsal sepal which together with the petals 
form a helmet-like structure. 
Syn.: Collea Lindl. in Bot. Reg. 9: sub t. 760, 1823, nom. 
reject. 
Type: Satyvrium adnatum Sw. 
Adnulla Raf., Fl. Tellur. 2: 87, 1837. 
Type: Satyvrium adnatum Sw. 
Sepals unequal, ringent; dorsal sepal concave to cucullate, 
together with petals form a distinct helmet-like structure; lateral 
sepals more or less porrect, decurrent on the protruding column- 
foot, basally connate into a ventricose, saccate or spur-like vesi- 
cle which is often manifested in a pronounced mentum. Petals 
connivent with dorsal sepal, decurrent or variously oblique at 
base. Lip fleshy, prominently unguiculate, fleshy-sagittate at 
base, rarely auriculate, lateral margins agglutinate with sides of 
column. Column rather stout, elongate, puberulent or pilose in 
front, basally produced in a decurrent foot which often pro- 
trudes from the wall of the ovary; stigmata 2, separate to va- 
riously approximate; rostellum rather soft, pliable, laminar, 
linear-oblong to ligulate, obtuse or truncate. Anther ovate- 
cordate, obtuse; pollinia clavate with a thick, ovate to suborbi- 
cular viscidium. Ovary cylindric to more or less fusiform, sessile 
or subsessile, somewhat twisted. 
Terrestrial herbs, rarely subaquatic or hydrophilous. Roots 
fasciculate, fleshy, stipitate to fusiform. Leaves when present 
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