A New Variety of Trillium Pusillum (Liliaceae) from the Virginias

A montane population of Trillium pusilum Michx. from the crest of Shenandoah Mountain on the Virginia-West Virginia state line is newly described as T. pusillum var. monticulum. It differs from the related coastal plain variant, var. virginianum Fernald, by its broader and shorter leaf and sepal ratios, typically notched petal apices, consistently sessile flowers (not at all pedicellate), slightly shorter style, and reduced stature. The var. monticulum is restricted to the ridge crest of the mountains at 1190 m (3900 ft) elevation while the var. virginianum is restricted to the coastal plains of eastern Maryland and Virginia at elevations less than 30 m (100 ft).