Distribution: Occurring east of the Cascades crest in far southeastern Washington; southeastern Washington to western Montana, possibly also in southern British Columbia, southern Alberta, and northwestern Wyoming.
Habitat: Basalt outcrops and seeps in grasslands.
Flowers: May-July
Origin: Native
Growth Duration: Annual
Conservation Status: Threatened in Washington (WANHP)
Annuals with fibrous roots or threadlike taproot; stems 5-17 cm, erect to ascending, straight or sharply bent at nodes, typically heavily branched, 4-angled, sparse coverage of nearly unstalked glands, gland-tipped hairs to 0.2 mm.
Leaves cauline, basal leaves not persistent; petiolate, 8-20 mm; blade broad-ovate to lanceolate, 8-25 mm long and 5-19 mm broad, venation palmate, wedge-shaped base, margins toothed or somewhat finely toothed, apex acute to obtuse, surfaces glandular and hairy as stems.
Axillary flowers 1-10, emerging from nodes throughout; fruiting pedicels glandular-hairy as stems, 10-22 mm; calyx tubular-campanulate, sometimes weakly inflated, 6-8 mm, margins with distinct serration or lobes, sparsely covered with minute stalked glands or not; corolla yellow with occasional small white patches, lower limb with several brownish spots, bilaterally symmetric and distinctly bilabiate; tube-throat broadly funnel-shaped, generally 8-12 mm, protruding beyond calyx margin; lobes obovate-oblong with rounded or truncate apexes; styles glabrous; anthers not protruding, glabrous.
Capsules 5-6 mm, included.
PNW Herbaria: Specimen records of Erythranthe ampliata in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Erythranthe ampliata checklist entry
OregonFlora: Erythranthe ampliata information
E-Flora BC: Erythranthe ampliata atlas page
CalPhotos: Erythranthe ampliata photos