J. Bot. Res. Inst. Texas 1: 163, figs. 3C,F, 8. 2007.
Annuals. Stems erect, simple or few-branched, (7–)10–21(–30) cm, glabrous or glabrate proximally, sparsely glandular-puberulent distally. Leaves: blade linear to linear-lanceolate or lanceolate-elliptic, often falcate, (16–)18–30(–43) × (1–)2.5–5 mm, margins entire or with 1 or 2(or 3) pairs of blunt teeth distally, apex obtuse to acute, surfaces glabrous or glabrate. Pedicels slender, 7–14(–22) mm, length 0.5–1(–1.6) times bract, sparsely glandular-puberulent; bracteoles 2, 2–4.5 mm. Flowers: sepals distinct, lanceolate, 2.7–5 mm; corolla 7–9 mm, tube and limb white tinged with pink or purple, veins white to greenish white or lavender; style 3–4.6 mm. Capsules ovoid, 3.4–5.1 × 3–4.5 mm. Seeds 0.4–0.7 mm.
Phenology: Flowering Apr–Jun.
Habitat: Seeps, pools, and streams in limestone and dolomite glades, alvars, calcareous grasslands.
Elevation: 50–300 m.
Ont., Ala., Ill., Ky., Tenn., Tex.
Populations of Gratiola quartermaniae are concentrated in northern Alabama and central Tennessee. Disjunct populations are known from the Edwards Plateau of Texas, Will County, Illinois, and southeastern Ontario. D. Estes and R. L. Small (2007) discussed the distribution and ecology of G. quartermaniae.