Hammarbya paludosa (L.) Kuntze (Malaxis paludosa (L.) Sw.) is known from northern Minnesota and the Lake Superior region of Ontario, and could well occur in bogs and conifer swamps in northernmost Michigan. It is even smaller than either of our two species, but has 2–3 leaves.

1. Lip narrowly pointed at apex; raceme slender, elongate; pedicels 1–2 (–3) mm long.

M. monophyllos

1. Lip 2-lobed at apex (with an indistinct central tooth); raceme thickish, usually ± condensed and flattened or rounded at top; pedicels at maturity 3.5–8 mm long.

M. unifolia

All species found in Malaxis

Malaxis monophyllosWHITE ADDER'S-MOUTH 
Malaxis unifoliaGREEN ADDER'S-MOUTH 


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. October 19, 2017.