Phytoneuron 2012-39: 30. 2012.
Herbs, annual. Stems erect to ascending, 20–380 mm, 4-sided, glandular-pubescent. Leaves basal and cauline, relatively even-sized; petiole absent; blade elliptic to elliptic-ovate or obovate, 7–45 (–57) × 3–20 (–32) mm, margins crenate, plane, apex obtuse to rounded, surfaces glandular-pubescent. Pedicels 1.5–6 (–7) mm in fruit. Flowers 2 per node, or 1 or 2 per node on 1 plant, chasmogamous, sometimes cleistogamous. Calyces asymmetrically attached to pedicel, not inflated in fruit, 6–18 mm, densely glandular-pubescent, lobes unequal, adaxial longest, apex obtuse, ribs green, intercostal areas whitish. Corollas salverform-rotate, throat dark purplish brown without internal or external markings, lobes white with bold, purplish brown veins, palate ridges absent, tube-throat 6.5–18 mm, limb 4–16 mm diam., not bilabiate. Anthers included, glabrous. Styles glandular-puberulent. Stigmas included, lobes unequal, abaxial 6–8 times adaxial. Capsules (5.5–) 7–17 mm. 2n = 16.
Phenology: Flowering Mar–May.
Habitat: Rocky granitic slopes, granite rocks and outcrops, sandy granitic soils, blue oak, blue oak-grey pine, Douglas oak, Douglas oak-canyon live oak, and gray pine-Douglas oak woodlands, steep canyon slopes with box elder.
Elevation: 100–1300 m.
Diplacus pictus is known from Kern and Tulare counties in the Sierra Nevada foothills and Tehachapi Mountains.
Diplacus pictus and D. mohavensis have been treated together as Mimulus sect. Mimulastrum; molecular data (P. M. Beardsley et al. 2004) indicate that the two species are independently derived and that the similarities in corolla morphology are convergent. Diplacus pictus produces cleistogamous flowers in drought conditions.