Syst. Veg. 1: 101. 1817
Perennials. Stems erect or ascending, light grayish green distally, unbranched, (3–)8–50 cm, sparsely to densely villous-hirsute, sometimes also glandular-hairy. Leaves: blade elliptic to lanceolate or oblong-ovate, 8–40 × 5–20 mm, base cuneate, margins entire, dentate, or serrate, apex short-acuminate, surfaces sparsely to densely villous-hirsute or glabrous. Racemes 1, terminal, 5–40 mm, to 60(–150) mm in fruit, (2–)5–25-flowered, axis densely villous-hirsute and ± glandular-hairy; bracts linear to lanceolate, 1–8 mm. Pedicels erect, 2–10(–15) mm, ca. equal to subtending bract, densely villous-hirsute or glandular-hairy. Flowers: calyx lobes (2.5–)3–5.5(–7) mm, apex obtuse or acuminate, glabrous or densely glandular-hairy; corolla deep blue-violet or violet-purple to deep blue, rotate, 3–11 mm diam.; stamens 1–2 mm; style 0.8–4(–6) mm. Capsules compressed in cross section, oblong-obovoid, 4–6(–8) × (2.8–)4–5.5 mm, ca. as long as wide, apex emarginate, usually densely glandular-hairy. Seeds 10–50, straw colored, ellipsoid, flat, 0.7–1 × 0.4–1 mm, 0.05–1 mm thick, very minutely striate.
Subspecies 2 (2 in the flora).
Veronica wormskjoldii occurs in two cytotypes, a diploid (2n = 18) in western North America and a tetraploid (2n = 36) in eastern North America and Greenland. As demonstrated by D. C. Albach et al. (2006), the tetraploid is likely to be a hybrid of the diploid V. alpina and V. wormskjoldii. In that publication, species rank was used for simplicity, not as a taxonomic conclusion. However, subsequent morphological analyses in conjunction with preparing this treatment revealed that the large variation in the diploid V. wormskjoldii, also supported by the large number of varieties established within that taxon, make it nearly impossible to differentiate the two North American taxa morphologically. In cases where two taxa are morphologically undifferentiable, but karyologically and genetically distinct and geographically clearly separate, the rank of subspecies seems more appropriate.