Camissonia, sometimes commonly known as sun cup or sundrop, is a genus of annual and perennial plants in the evening primrose family Onagraceae. A total of 12 species are known, nearly all from western North America, especially in the California Floristic Province, but also one from South America. Previous circumscriptions of the genus had recognized up to 62 species before it was split among other closely related genera.Wagner WL, PC Hoch, and PH Raven. 2007. Revised classification of the Onagraceae. Systematic Botany Monographs, 83: 1-240.
The flowers generally open at dawn and are yellow. They are usually cup-shaped, thus the common name.
Formerly included in Oenothera, the species of Camissonia are distinguished by having a club- or head-shaped stigma, instead of the 4-part-divided stigma of Oenothera or Clarkia.
Camissonia species are used as food plants by the larvae of some Lepidoptera species including Schinia cupes and Schinia deserticola, both of which feed on C. claviformis, the latter exclusively.
The genus is named after the botanist Adelbert von Chamisso.
Selected species According to The Plant List, the genus includes the following accepted species:The Plant List
Camissonia andina (Nutt.) P.H.Raven Camissonia bairdii S.L.Welsh Camissonia benitensis P.H.Raven Camissonia breviflora (Torr. & A.Gray) P.H.Raven Camissonia campestris (Greene) P.H.Raven (Mojave suncup) Camissonia contorta (Douglas) Kearney Camissonia dentata(Cav.) Reiche Camissonia dominguez-escalantorum N.D.Atwood, L.C.Higgins & S.L.Welsh Camissonia graciliflora (Hook. & Arn.) P.H.Raven Camissonia hilgardii (Greene) P.H.Raven Camissonia integrifolia P.H.Raven Camissonia kernensis (Munz) P.H.Raven Camissonia lacustris P.H.Raven Camissonia ovata (Nutt. ex Torr. & A.Gray) P.H.Raven Camissonia palmeri (S.Watson) P.H.Raven Camissonia parvula (Nutt.) P.H.Raven Camissonia pubens (S.Watson) P.H.Raven Camissonia pusilla P.H.Raven Camissonia sierrae P.H.Raven Camissonia strigulosa (Fisch. & C.A.Mey.) P.H.Raven Camissonia subacaulis (Pursh) P.H.Raven Camissonia tanacetifolia (Torr. & A.Gray) P.H.Raven
References
Jepson Flora Project: Camissonia