Linaria arenaria DC., Icon. Pl. Gall. Rar. 1: 5, tab. 14 (1808).
Densely glandular-puberulent annual, sometimes perennating by root-buds; fertile stems usually numerous, 3.5-23 cm, ascending to erect, often branched above; sterile stems 0-6. Leaves of fertile stems 4-14 x 1.5-2.5 (-4.5) mm, oblanceolate to elliptic, acute or obtuse, flat, in whorls of 3-4 below, alternate above; leaves of sterile stems similar but usually shorter and in whorls of 3-4. Inflorescence with 2-11 flowers, somewhat dense in flower, lax in fruit. Bracts 3-8 mm, linear-oblanceolate, acute. Pedicels 0.5-2.5 mm in flower and fruit, erecto-patent to erect. Calyx-lobes subequal, 2.5-5 x 0.8-1.4 mm, ovate to oblanceolate, acute. Corolla 4-8 mm, dull yellow or the spur sometimes violet; tube slender; adaxial lip sinus 0.6-1 mm; abaxial lip sinus 0.2-0.3 mm; spur 1.5-3 mm, slender, straight, shorter than rest of corolla. Capsule 3-5 mm, oblong-ovoid, glandular-pubescent. Seeds (0.8-) 1-1.5 mm, reniform-orbicular or reniform, biconvex or plano-convex, black and shiny; hilum narrow; wing 0.05-0.1 mm broad, thin or thickened towards disc, not clearly differentiated from disc, smooth, not papillate; disc smooth without tubercles or papillae; periclinal wall of testa-cells tabular, verrucate, the amticlinal walls of testa-cells angular with ridge over junction. Modified from Sutton (1988).
Mainly W France, N Spain?, probably introduced to Britain. Ga Hs? [Br] .
Type: FRANCE: Côtes de Bretagne Petit Thouars s.n. (lecto. (Valdés, 1970a: 262, 264) G-DC).