Corallorhiza maculata var. occidentalis (Lindley) Ames 1924

The variety Corallorhiza maculata var. occidentalis was first described by Lindley (1840) as a variety of C. multiflora which is closely related C. maculata. Cockerell (1903) proposed a new species, Corallorhiza grabhamii, from Pecos, New Mexico and Suksdorf (1906) coined C. leimbachiana from Bingen, Washington. There was reason to discuss whether all these species could be summarized in an eastern and western clade (Cockerell 1916). Cockerell (1916) therefore proposed a subspecies Corallorhiza maculata subsp. occidentalis and finally Ames (1924) subsumed all proposed names as a variety, Corallorhiza maculata var. occidentalis, which is the accepted name by WCSP (2021). It occurs from the west to the northeast of the United States of America (POWO 2021). It often occurs together with C. maculata var. maculata and can be distinguished by its earlier flowering of nearly 3 weeks and that the midlobe of the labellum is distinctly expanded and floral bracts are in average longer than 1.5 mm. From the variety C. maculata var. mexicana it can be identified by the labellum which is throughout spotted in the expanded portion of mid-lobe, while the other is primarily spotted at the margins (Freudenstein 1997).