Flora of North America species comparison

Goodyera tesselata is almost completely restricted to once-glaciated areas in the Great Lakes region, the northeastern United States, and adjacent Canada.

Goodyera tesselata tends to be taller and to have larger leaves, more cauline bracts, more flowers, and longer perianths than Goodyera repens. Although overlap exists in any count or measurement, the two are, for the most part, easily distinguishable. Some of the difficulty in identifying ambiguous specimens is explained by the hypothesis (J. A. Kallunki 1976) that G. tesselata itself is intermediate between and a probable allotetraploid of G. repens with white-reticulate leaves and G. oblongifolia. Because the tetraploids and the triploid hybrids (2n = ca. 45) cannot be distinguished with certainty by their morphology, the description here includes individuals of both tetraploid and triploid individuals. In the extreme, individuals of G. tesselata (in the broad sense) approach G. repens more often than G. oblongifolia, and it is sometimes impossible to distinguish some triploids from G. repens with white-reticulate leaves.

(Discussion copyrighted by Flora of North America; reprinted with permission.)