The Onagraceae are a family of flowering plants known as the willowherb family or evening primrose family. They include about 650 species of herbs, shrubs, and treesOnagraceae. Flora of China. in 17 genera. The family is widespread, occurring on every continent from boreal to tropical regions.
The family includes a number of popular garden plants, including evening primroses (Oenothera) and fuchsias (Fuchsia). Some, particularly the willowherbs (Epilobium), are common weeds in gardens and rapidly colonize disturbed habitats in the wild. One such species is fireweed (Chamaenerion angustifolium).
The family is characterised by flowers with usually four sepals and petals; in some genera, such as Fuchsia, the sepals are as brightly coloured as the petals.
The seeds are generally very small. In some genera, such as Epilobium, they have tufts of hairsEpilobium. Flora of China. and are dispersed on the wind. In others, such as Fuchsia, the seeds develop in juicy berries dispersed by animals. The leaves are commonly opposite or whorled, but are spirally arranged in some species; in most, they are simple and lanceolate in shape. The pollen grains in many genera are loosely held together by viscin threads. Most bees cannot collect it, and only bees with specialized morphologies can effectively pollinate the flowers; nearly all bee taxa that visit the flowers are oligoleges specialized on the family Onagraceae.
The family was named after the genus Onagra (now known as Oenothera) in 1836 by John Lindley in the second edition of A Natural System of Botany.
Distribution
Onagraceae species are found on every continent except Antarctica, although diversity is highest in California and adjacent areas. Most species are found in temperate climates.Govaerts R (ed.). 2024. WCVP: World Checklist of Vascular Plants. Facilitated by the Royal Botanic Gardens, Kew. [WWW document] URL http://sftp.kew.org/pub/data-repositories/WCVP/ [accessed 31 Aug 2026].
Genera
Subfamily Ludwigioideae Ludwigia L.
Subfamily Onagroideae Tribe Circaeeae Circaea L. Fuchsia L. Hemifuchsia Christian Geier, Johannes M. Bouchal, Silvia Ulrich, Dieter Uhl, Torsten Wappler, Sonja Wedmann, Reinhard Zetter, Jürg Schönenberger, Friðgeir Grímsson (2023). Potential pollinators and paleoecological aspects of Eocene Ludwigia (Onagraceae) from Eckfeld, Germany. Palaeoworld, 2023, ISSN 1871-174X, https://doi.org/10.1016/j.palwor.2023.07.003. Tribe Epilobieae Chamaenerion Ség. Epilobium L. Tribe Gongylocarpeae Gongylocarpus Schltdl. & Cham. Tribe Hauyeae Hauya DC. Tribe Lopezieae Lopezia Cav. Megacorax Elizondo et al. Tribe Onagreae Camissonia Link Camissoniopsis W.L.Wagner & Hoch Chylismia (Torr. & A.Gray) Raim. Chylismiella (Munz) W.L.Wagner & Hoch Clarkia Pursh Eremothera (P.H.Raven) W.L.Wagner & Hoch Eulobus Nutt. ex Torr. & A.Gray Gayophytum A.Juss. Neoholmgrenia W.L.Wagner & Hoch Oenothera L. Taraxia (Torr. & A.Gray) Raim. Tetrapteron (Munz) W.L. Wagner & Hoch Xylonagra Donn.Sm. & Rose
Several genera are synonymized but appear often in older literature as belonging to the previous genera. For example Calylophus and Gaura, which have both been absorbed into Oenothera. Likewise Eucharidium is a synonym of Clarkia.
Gallery
References
External links
Smithsonian Institution: Onagraceae classification