Corolla lobes above scarlet, red, orange, pink, lilac or rarely light blue and very infrequently white, paler beneath with dark venation, intrusions between lobes paler or white; tube greenish red to purplish white, tube and lobes beneath sparsely papillate, tube often slightly bent, altogether (2.4)3–5(5.5) mm. long, the dilated part (1.3)1.6–2.6(3) x (0.4)0.5–0.9(1.1) mm., the narrow part (0.2)0.3–0.7(0.8) mm. wide; lobes (1.4)1.5–4.3(5.6) x (0.8)0.9–2.3(2.5) mm., oblong-elliptic, subacute.
Leaves (9.2)12–55(65) x (0.5)1.1–4(4.9) mm., linear to linear-lanceolate, margins and lower midrib papillate, lower surface scabrid or glabrous, apex acute, narrowed to the base; stipular sheath (0.2)0.7–2.8(3.8) mm. long, stipular lobes (0.5)0.8–3.7(6.7) mm. long.
Calyx tube (1.2)1.4–2.2(2.5) x (0.9)1.1–1.6(1.8) mm., ellipsoid, densely papillate; lobes (1.4)1.8–4.2(5.1) mm. long and (0.2)0.3–0.5(0.75) mm. wide at the base, narrowly triangular to linear, margins scabrid.
Inflorescences ± many-flowered, 2 flowers at a node, one ± sessile, the other pedicellate; peduncles (3.2)6.8–11.9(16.5) mm. long, papillate; (pseudo-) pedicels (0.6)1–3.6(6.7) mm. long, densely papillate.
Capsules (2.1)2.6–5(5.2) x (2.3)2.8–4.3(4.7) mm., oblong-elliptic, scabrid to sparsely papillose, ribs often purplish.
Annual erect unbranched to sparsely branched herbs 5–45(70) cm. tall; stems ± papillate.
Style and stigma as long as narrow part of the tube; stigma lobes 0.8–1.8 mm. long.
Flowers few in lax inflorescences, bright scarlet, sometimes pink, mauve or white
Anthers narrowly ovoid, c. 1–2 mm. long; pollen (3)4–5-colporate.
Slender erect herb a few inches to 1 ft. high, with few branches
Seeds light brown, c. 0.4–0.5 mm. long, angular-subconic.