Annuals, taprooted. Stems erect, simple or branched from basal nodes, 2–14.5 cm, sparsely glandular-pubescent, internodes elongate, distinct. Leaves cauline, basal not persistent; petiole 0 mm; blade 1-veined or palmately 3-veined (in broader ones), linear to lanceolate, 5–15 × 0.5–2 mm, base attenuate, margins entire, apex acute to obtuse, surfaces sparsely glandular-pubescent. Flowers herkogamous, 1–30, from distal or medial to distal nodes. Fruiting pedicels ascending to often spreading horizontally, (5–)9–25 mm. Fruiting calyces sometimes red-dotted on ribs, campanulate, 3–6 mm, margins distinctly toothed or lobed, glabrous, sparsely glandular-pubescent, ribs weak, lobes pronounced, erect, margins glabrous. Corollas bicolored (abaxial limb yellow with red spots, adaxial maroon-purple) or yellow, bilaterally symmetric, strongly bilabiate; tube-throat cylindric, (5–)8–15 mm, exserted beyond calyx margin; limb expanded 6–15 mm, lateral lobes 2-fid, palate bearded. Styles glabrous. Anthers included, glabrous. Capsules included or equal to calyx, 3–5 mm.
Phenology: Flowering May–Aug.
Habitat: Open areas in pine forests, edges of meadows and ephemeral streams.
Elevation: 1800–3400 m.
Erythranthe barbata previously has been placed in synonymy with E. montioides but differs from it in having each corolla lobe deeply notched and a consistently bearded palate. In E. montioides, each corolla lobe is entire or shallowly notched, and the palate is glabrous or sparsely bearded. Erythranthe barbata is most abundant in Tulare County but also occurs in immediately adjacent Inyo and Kern counties.