San Benito suncup

Herbs villous and also glandular puberulent distally. Stems erect or decumbent, slender, wiry, usually branched, 3–20 cm. Leaves: proximalmost not clustered near base, green or slightly bluish green; blade very narrowly elliptic, 0.7–2 × 0.1–0.3 cm, base cuneate or attenuate, margins sparsely serrulate, apex acute. Flowers opening near sunrise; floral tube ca. 1.2 mm, moderately to very sparsely pubescent inside on prox­imal 1/2; sepals 3.2–3.5 mm, reflexed in pairs; petals 3.5–4 mm, each ± with 2 red dots basally; episepalous filaments 2 mm, epipetalous filaments 1.2 mm, anthers 0.3–0.6 mm, pollen with usually less than 10% of grains 4-pored; style 2.1–2.5 mm, stigma surrounded by anthers at anthesis. Capsules 15–45 × 0.8–1.3 mm; subsessile. Seeds 0.6–0.8 × 0.3–0.4 mm. 2n = 28.

Flowering Apr–Jul. Sandy or gravelly serpentine soil on alluvial terraces and sandy or gravelly serpentine soil in upland areas in geologic interfaces between ser­pentine and non-serpentine rock types in Quercus douglasii and Juniperus californicus woodlands; of conservation concern; 600–1400 m; Calif.

Camissonia benitensis is known from New Idria and nearby serpentine areas, lower Clear Creek drain­age and San Carlos Creek, San Benito County, and is reported from adjacent Fresno and Monterey counties. More than 50,000 individuals are known, but their habitat is threatened by off-road vehicles.

P. H. Raven (1969) determined that Camissonia benitensis is a self-compatible tetraploid and auto­gamous, also stating that C. benitensis is most likely closely related to C. strigulosa.