Chimaphila umbellata is morphologically variable across its extensive range. Six subspecies have been recognized widely in the literature: subsp. acuta in the southwestern United States, subsp. cisatlantica in eastern North America, subsp. domingensis (S. F. Blake) Dorr in Hispaniola, subsp. mexicana (de Candolle) Hultén in Mexico, and subsp. umbellata in Eurasia. S. F. Blake (1917), in discussing the complex, stated, '...while the differential characters brought forward for their specific separation are confined to differences in size, in the prominence of the venation, the shape of the sepals, the direction of the pedicels, and the rotundity of the stem, characters which are not only rather obscure but at best are merely comparative, and are shown by the material examined to be by no means absolutely constant.' Hiroshi Takahashi (1987), who did not consider subsp. domingensis, found broad overlap in most morphologic characters used to distinguish the subspecies. Extreme forms of the spectrum of morphologic expression may be distinctive; variation among the taxa appears to be clinal. Only subsp. domingensis, which is geographically isolated on Hispaniola and has glabrous peduncles and pedicels, glabrous filaments, and relatively small leaves, appears to be sufficiently distinct from the rest of the species to warrant recognition (L. J. Dorr 1995). It also has rugulate pollen; other taxa included here within subsp. umbellata have psilate pollen (Takahashi 1986b).

Plant: perennial, rhizomatous, evergreen sub-shrubs Leaves: generally many per node; blades oblanceolate, 3-7 cm long, toothed; upper surface dark green, veins not white-bordered; lower surface pale green INFLORESCENCE: inflorescence bracts linear-lanceolate, fragile Flowers: 3-10; actinomorphic, sepals broadly ovate, about 2 mm long; apex mainly rounded; margins fringed; petals pink to red, 6-8 mm long; filament enlargement lightly hairy on margins only; anthers 2.5-3.0 mm long Fruit: FRUITS erect capsules, without fibers connecting opened valves Misc: Coniferous forests; 1800-2900 m (6000-9500 ft); Jun-Aug Notes: scapes to 30 cm tall, minutely papillate, becoming densely glandular papillate in the inflorescence REFERENCES: Haber, Erich. 1992. Pyrolaceae. Ariz.-Nev. Acad. Sci. 26(1)2.