Ann. Nat. Hist. 1: 137. 1838.
Subshrubs or shrubs. Stems erect to ascending-erect or sprawling, 200–1500 (–2000) mm, glabrous. Leaves cauline, relatively even-sized; petiole absent; blade linear-oblong or narrowly elliptic to narrowly lanceolate or oblanceolate, 10–60 × 1–11 (–15) mm, margins entire or serrate, plane or revolute, apex acute, surfaces glabrous. Pedicels 5–25 mm in fruit. Flowers 2 (–4) per node, chasmogamous. Calyces not inflated in fruit, 17–25 mm, glabrous, lobes unequal, apex acute, ribs green, intercostal areas light green. Corollas deep red, orange-red, or orange to maroon, throat sometimes orangish, palate ridges red, rarely yellow, tube-throat 27–35 mm, limb 15–23 mm diam., bilabiate, lobes oblong, apex truncate, sometimes notched. Anthers (distal pair) exserted, glabrous. Styles minutely glandular. Stigmas exserted, lobes equal. Capsules 14–22 mm. 2n = 20.
Phenology: Flowering Jan–Jul(–Oct).
Habitat: Rocky hillsides, boulders, moist hillsides, canyons, wash bottoms, roadsides, chaparral.
Elevation: (20–)100–700 m.
Calif., Mexico (Baja California)
Diplacus puniceus occurs in southwestern California and northeastern Baja California. Hybrids are common with D. longiflorus and have been called D. ×australis.