1. Trientalis Linnaeus, Sp. Pl. 1: 344. 1753; Gen. Pl. ed. 5, 161. 1754.
Starflower [Latin, one-third of a foot, alluding to height]
Anita F. Cholewa
Herbs, perennial, not succulent, glabrous or glandular; resin canals rarely obvious. Rhizomes slender or tuberous; roots fibrous. Stems erect, usually simple. Leaves in terminal whorl or cluster, dimorphic, with smaller cauline and alternate ones proximally (some ± scalelike); petiole present (distal) or absent (proximal); blade lanceolate or oblanceolate to elliptic, suborbiculate, obovate, or spatulate, base cuneate, margins entire, plane, apex acuminate, acute, or obtuse to rounded, surfaces glabrous. Inflorescences axillary in distal leaves, solitary flowers. Pedicels present. Flowers: sepals (5-)7(-9), green, calyx lobes lanceolate or lanceolate-linear, much longer than tube; petals (5-)7(-9), corolla white to pink, rose, or pinkish lavender, rotate, lobes longer than tube, apex acute or acuminate; stamens (5-)7(-9); filaments connate basally. Fruits capsular, globose, dehiscence valvate. Seeds 2-15, black or reddish brown, globose, with deciduous, white, netlike covering. x = 35, 42.
Species 3 (3 in the flora): n North America, Eurasia.
The number of species recognized in treatments of Trientalis has varied from two to four; in some, only T. europaea and T. borealis have been recognized, sometimes T. latifolia has also been recognized, while other authors have segregated the northern Pacific populations of T. europaea as T. arctica. We consider only three to be solid species.