Onagraceae tribe Circaeeae
FFl. Belg., 88. 1827.
Herbs, perennial, or shrubs, [epiphytes, lianas, or trees]. Leaves opposite or whorled, [alternate]; stipules present. Flowers primarily protogynous, actinomorphic and 4-merous, or zygomorphic and 2-merous; stamens 2 times as many, or as many, as sepals; pollen shed in monads. Fruits indehiscent, either a fleshy berry or a dry capsule, covered with stiff, hooked hairs. Seeds 1–500, without hairs or wings.
Discussion
Genera 2, species 117 (2 genera, 4 species, including 1 hybrid, in the flora): North America, Mexico, West Indies (Hispaniola), Central America, South America, Eurasia, n Africa, Pacific Islands (New Zealand, Society Islands).
All previous classification systems have placed Circaea and Fuchsia into different tribes, based on their morphological and geographical differences. Molecular analyses place these genera into a single clade (C. J. Bult and E. A. Zimmer 1993; E. Conti et al. 1993; R. A. Levin et al. 2003, 2004; V. S. Ford and L. D. Gottlieb 2007) that is as or more strongly supported than are other clades. The two genera share the feature of indehiscent fruits, expressed in Fuchsia as fleshy berries and in Circaea as dry fruits covered with hooklike hairs; nonhomologous indehiscent fruits also occur in Onagreae. The only occurrences of protogyny in the family occur in these two genera (not in all species of either, P. H. Raven 1979).
Selected References
None.