Camissonia hardhamiae P. H. Raven, Contr. U.S. Natl. Herb. 37: 301, fig. 47. 1969

Herbs annual, villous, also glandular puberulent distally. Stems erect, with 1 or more branches from basal rosette, to 60 cm. Leaves 1–12 × 0.4–1.8 cm; subsessile; blade lanceolate, narrowly elliptic, or narrowly ovate, base truncate, margins dentate, apex acute. Flowers opening near sunrise; floral tube 1.7–2 mm; sepals 1.8–3.2 mm; petals yellow, immaculate, 2–4 mm; episepalous filaments 1.5–2 mm, epipetalous filaments 1–1.5 mm, anthers 0.7 mm, 70–100% of pollen grains 4- or 5-pored; style 3–4 mm, stigma surrounded by anthers at anthesis. Capsules straight or 1-coiled, subterete in living mater­ial, obscurely 4-angled when dry, 13–25 × 1.3–1.6 mm. Seeds 0.7–1.1 mm. 2n = 42.

Flowering Mar–May. Sandy soils, limestone, disturbed oak woodlands; of conservation concern; 150–1000 m; Calif.

Camissoniopsis hardhamiae is narrowly endemic to the Outer South Coast Ranges. Populations are very local, known only from a few localities in sandy soil in disturbed oak woodland, southernmost Monterey to central San Luis Obispo County. P. H. Raven (1969) determined C. hardhamiae to be self-compatible and primarily autogamous. The species is apparently a hexaploid derived via hybridization between the tetraploid C. intermedia (2n = 28) and the diploid C. micrantha (2n = 14).