Clarkia affinis
Madroño 12: 34. 1953.
Stems erect, to 80 cm, puberulent. Leaves: petiole 0–3 mm; blade linear to narrowly lanceolate, 1.5–7 cm. Inflorescences dense spikes, axis straight; buds erect. Flowers: floral tube1.5–4 mm; sepals reflexed together to 1 side; corolla bowl-shaped, petals 5–15 mm; stamens 8, subequal; ovary cylindrical, 8-grooved, length at least 10 times width; stigma not exserted beyond anthers. Capsules 15–30 mm, beak 3–7 mm; pedicel 0–5 mm. Seeds brown or gray, 1–1.5 mm, scaly, crest 0.1 mm. 2n = 52.
Phenology: Flowering Apr–Jun.
Habitat: Openings in woodlands and chaparral.
Elevation: 0–500 m.
Discussion
Clarkia affinis is known primarily from west-central California and the North Coast Ranges, and more scattered in the Sierra Nevada Foothills and Western Transverse Ranges.
Clarkia affinis is a hexaploid most closely related to C. purpurea; both have 2n = 52. Chromosome pairing in hybrids between them, as well as morphology, suggest that they have a tetraploid (2n = 34) genome in common. The two species are most readily distinguished by their immature capsules, which in C. affinis are slender, at least ten times longer than wide, beaked, and shallowly grooved, whereas those of C. purpurea are stout, not more than eight times longer than wide, not prominently beaked, and deeply grooved; the sepals of the former are generally reflexed together in fours whereas those of the latter are reflexed individually or in twos. Based on morphology and molecular data, the diploid genome probably came from C. cylindrica or a related species.
Selected References
None.