Nemesia aurantia K.E.Steiner

Annual herb up to 410 mm tall, simple or branching; stems glandular pilose, rectangular in cross section, corners ridged, sides up to 2 mm wide, lateral stems up to 265 mm long. Leaves simple, opposite, glabrous, apices acute, bases cuneate to truncate, margins sparsely dentate; basal leaves ovate to elliptical, 10.8-18.4 x 3.1-8.4 mm; petioles up to 7 mm long; upper leaves sessile, lanceolate to linear, 9.0-39.6 x 1.3-9.4 mm, glabrous. Inflorescence terminal, racemose, up to 190 mm long, or flowers axillary; bracts alternate, sessile, reflexed, narrowly lanceolate to deltoid, 1.1-2.4 x 0.9 mm, glabrous above, sparsely glandular puberulent below, apex acute, base truncate; margins entire; pedicels ± 8-24 mm long, ascending, glandular pilose. Calyx lobes 5, spreading, acute, densely glandular pilose, upper and lateral lobes oblong, ± 2.5 x 0.8 mm, lower lobes shorter, lanceolate, ± 2.1 x 0.8 mm. Corolla bilabiate, 13.1-18.8 x 11.1-16.0 mm, upper lip 4-lobed, 2 inner lobes oblong to obovate, 5.1-6.2 x 1.9-3.2 mm, apices rounded to acute, bases strongly oblique, 2 outer lobes spreading, oblong, 4.7-6.5 x 3.4-4.1 mm, apices emarginate, bases strongly oblique; all lobes orange distally and pale yellow with brownish streaks at base, lower lip widely obcordate, 9.2-12.3 x 10.5-16.0 mm, deep orange, basal portion inflated into a dark brown, convex palate, 4.1-8.0 x 4.5-5.2 mm long; bosses 2, oblong, divergent, orange, 0.5-1.7 x 1.3-1.4 mm, densely villous, trichome stalks pale yellow or brown, translucent, simple or branched below head, heads capitate or discoid; hypochile (floor of corolla tube) ± 3.7-4.1 x 4 mm, ± flat, streaked with reddish brown, sparsely to densely pilose, especially on inner lateral walls, outer surface glandular pilose; upper inside surface of corolla tube pale yellow with brown lines, base shallowly saccate, 0.7-1.0 x 4.7-4.9 mm, pale yellow, lower outside portion pilose. Stamens 4, lying in a shallow depression in upper inside surface of corolla tube; filaments of anticous pair (twisted into posticous position) ± 2.2 mm long, sigmoid, ± straight in middle, glabrous; posticous filaments ± 1.5 mm long, straight except at base, glabrous; anthers ± 1.1-1.2 mm long, each pair strongly coherent, opening downward. Ovary oblong-ovoid, ± 1.0-1.2 x 0.9-1.0 mm, laterally compressed; style ± 0.5 mm, deflected away from corolla opening, oblong, truncate, lying between anther pairs; stigma deltoid ± 0.3 x 0.5 mm. Capsules ovate to oblong in outline, ± 3.8-8.3 x 4.5-7.0 mm, compressed contrary to septum, apex emarginate to bilobed, lobes acute to rounded. Seeds winged, ovate to widely ovate, 1.7-2.4 x 1.3-2.1 mm, outer layer of testa white, lacey, verruculate, enveloping inner seed at maturity, wing membranous with numerous parallel white veins, internal portion of seed narrowly elliptical, dark brown, 1.0-1.2 mm long, surface alveolate.