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Corallorhiza

Reference: Magrath and Freudenstein (2002).

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C. odontorhiza
1a. Labellum without lateral lobes; lateral sepals up-curved; plants flowering late-August through late September
See list of 2 species in 1b
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1b. Labellum with a lateral lobe or tooth on each side [Fig. 162]; lateral sepals spreading to down-curved; plants flowering mid-May through late-August
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  C. maculata
  2a. Labellum (3.5–) 4–9 mm long, white spotted with red-purple (rarely pure white)   [Fig. 162]; sepals and lateral petals with 3 (–5) nerves; spur present, though inconspicuous; stem commonly purple to brown; plants flowering in early July through late August; raceme with (6–) 10–30 (–41) flowers
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  C. trifida
  2b. Labellum 2–3.3 (–5) mm long, white; sepals and lateral petals with 1 nerve; spur  absent; stem commonly yellow-green; plants flowering in mid-May through mid-June; raceme with 3–12 (–18) flowers

Show photos of: Each photo represents one species in this genus.