Smithsonian National Museum of Natural History

Onagraceae - The Evening Primrose Family

Click on taxonomic name for list.
Xylonagra arborea Chylismia claviformis subsp. lancifolia Epilobium ciliatum watsonii Oenothera riskindii Gayophytum diffusum subsp. diffusum Chamerion angustifolium subsp. circumvagum Taraxia subacaulis Fuchsia pringsheimii Camissoniopsis bistorta Lopezia grandiflora subsp. macrophylla Hauya elegans subsp. cornuta Clarkia breweri Megacorax gracielanus Ludwigia peploides subsp. glabrescens Circaea lutetiana subsp. canadensis Eulobus californicus Gongylocarpus fructiculosus Tribe Hauyeae Tribe Circaeeae Tribe Lopezieae Tribe Gongylocarpeae Tribe Epilobieae Tribe Onagreae Neoholmgrenia Camissoniopsis Tetrapteron Camissonia Eremothera Oenothera Chylismia Subfamily Ludwigioideae Subfamily Onagroideae Eulobus Taraxia Chylismiella Gayophytum Clarkia Xylonagra Epilobium Chamaenerion Gongylocarpus Megacorax Lopezia Circaea Fuchsia Hauya Ludwigia
Oenothera glaucifolia


In the site we present a full checklist of all taxa within each of the 18 recognized genera as well as diagnostic images for as many taxa as possible.

The new classification is based on a number of phylogenetic and revisionary publications and results of a recent project initiated at the Smithsonian Institution. A group of Onagraceae researchers worked together to gain a better understanding of the evolution of the family and to derive an appropriate classification. Using molecular, morphological, biochemical, and biogeographic tools, results have provided new insights into family relationships and monophyletic groups at the tribal and generic levels.

Four papers were published from this project. A more complete bibliography for the Onagraceae family is provided.

    Katinas, L., J. Crisci, W.L. Wagner, & P.C. Hoch. 2004. Geographical diversification of tribes Epilobieae, Gongylocarpeae, and Onagreae (Onagraceae) in North America, based on parsimony analysis of endemicity and track compatibility analysis. Ann. Missouri Bot. Gard. 91: 159-185. (pdf)

    Levin, R.A., W.L. Wagner, P.C. Hoch, M. Nepokroeff, J.C. Pires, E.A. Zimmer, & K.J. Sytsma. 2003. Family-level relationships of Onagraceae based on chloroplast rbcL and ndhL data. Amer. J. Bot. 90: 107-115. (pdf)

    Levin, R.A., W.L. Wagner, P.C. Hoch, W.J. Hahn, A. Rodriguez, D.A. Baum, L. Katinas, E.A. Zimmer, & K.J. Sytsma. 2004. Paraphyly in Tribe Onagreae: Insights into phylogenetic relationships of Onagraceae based on nuclear and chloroplast sequence data. Syst. Bot. 29: 147-164. (pdf)

    Wagner, W.L. 2004. Resolving a nomenclatural and taxonomic problem in Mexican Oenothera sect. Hartmannia (Tribe Onagreae, Onagraceae). Novon 14: 124-133. (pdf)

Smithsonian Mellon Fellows:
  Jorge V. Crisci, Museo de La Plata
  Peter C. Hoch, Missouri Botanical Garden
  Liliana Katinas, Museo de La Plata
  Rachel A. Levin, Smithsonian postdoc
  Robert A. Raguso, University of South Carolina -Columbia
  Kenneth J. Sytsma, University of Wisconsin -Madison

Smithsonian Scientists:
  Warren L. Wagner, Curator of Pacific Botany
  Elizabeth A. Zimmer, Curator, Laboratories of Analytical Biology

Junior Fellows:
  Richard Clinebell, Missouri Botanical Garden

This web site was conceived by Warren L. Wagner and co-written with Peter C. Hoch. Site development was by Denise Mix with assistance from Jessica Braun and Jamie Whitacre in content management and database maintenance. Click here for information on how to reference this Web site.
Fuchsia splendens


Despite intensive morphological and molecular studies of Onagraceae, relationships within the family have not been fully understood. One drawback of previous molecular analyses was limited sampling within the large tribe Onagreae. In addition, the monophyly of two species-rich genera in Onagreae, Camissonia and Oenothera, has never been adequately tested. To understand relationships within Onagraceae, test the monophyly of these two genera, and ascertain the affinities of the newly discovered genus Megacorax, parsimony and maximum likelihood analyses with rbcL and ndhF sequence data for 24 taxa representing all 17 Onagraceae genera and two outgroup Lythraceae were conducted [Levin et al. 2003 (pdf)]. Results strongly support a monophyletic Onagraceae, with Ludwigia as the basal lineage and a sister-taxon relationship between Megacorax and Lopezia. Gongylocarpus is supported as sister to Epilobieae plus the rest of Onagreae, although relationships within the latter clade have limited resolution. Thus, we advocate placement of Gongylocarpus in a monogeneric tribe, Gongylocarpeae. Most relationships within Onagreae are weakly resolved, suggesting a rapid diversification of this group in western North America. Neither Camissonia nor Oenothera appears to be monophyletic. Morphological characters generally agree with the molecular data, providing further support for relationships.

In a second study study [Levin et al. 2004 (pdf)], DNA sequence data from one nuclear region (ITS) and two chloroplast regions (trnL-trnF and rps16) were used to infer phylogenetic relationships among 93 taxa, with concentrated sampling in the large tribe Onagreae. Results strongly support tribe Gongylocarpeae as sister to tribes Epilobieae + Onagreae, both of which are monophyletic. Within Onagreae, Camissonia appears to be broadly paraphyletic, as does Oenothera. In Oenothera there appear to be two lineages, one of which has Calylophus and Gaura + Stenosiphon nested within it. At the base of the Onagraceae phylogeny, we have clarified previous confusion regarding conflicting placements of Hauya and Lopezia based on nuclear versus chloroplast data. Results of these analyses suggest the need for new taxonomic delimitations that will be presented in comprehensive revised classification of the family Onagraceae based on molecular sequence data and morphology by W. L. Wagner, P. C. Hoch and P. H. Raven.

Onagraceae Bibliography


Abdel-Hameed, F. & R. Snow. 1972. The origin of the autotetrapolid Clarkia gracilis. Evolution 26: 74–83.

Adanson, M. 1763. Onagrae. In Familles des Plantes, 2: 81–85. Chez Vincent, Paris.

Arroyo, M. & P. H. Raven. 1975. The evolution of subdioecy in morphologically gynodioecious species of Fuchsia sect. Encliandra (Onagraceae). Evolution 29: 500–511.

Astatt, P. & P. Rundel. 1982. Pollinator maintenance vs. fruit production: partitioned reproductive effort in subdioecious Fuchsia lycioides. Ann. Missouri Bot. Gard. 69: 199–208.

Averett, J. E., S. Huang, & W. L. Wagner. 1987. Flavonoid analysis of Oenothera speciosa (Onagraceae). Southw. Naturalist 32: 117–120.

_____. 1988. Flavonoid survey of Oenothera (Onagraceae): Sects. Gauropsis, Hartmannia, Kneiffia, Paradoxus and Xylopleurum. Amer. J. Bot. 75: 476–483.

Averett, J. E. & P. H. Raven. 1983. Flavonoids of Stenosiphon (Onagraceae). Phytochemistry 22: 1680–1681.

_____. 1984. Flavonoids of Onagraceae. Ann. Missouri Bot. Gard. 71: 30–34.

Averett, J. E., W. L. Wagner, & S. Huang. 1991. The flavonoids of Oenothera sect. Megapterium (Onagraceae). Biochem. Syst. Evol. 19: 87–89.

Baker, H. G. & I. Baker. 1982. Starchy and starchless pollen in the Onagraceae. Ann. Missouri Bot. Gard. 69: 748–754.

Baum, D. A., K. J. Sytsma, & P. C. Hoch. 1994. The phylogeny of Epilobium (Onagraceae) based on nuclear ribosomal DNA sequences. Syst. Bot. 19: 363–388.

Berry, P. E. 1982. The systematics and evolution of Fuchsia sect. Fuchsia (Onagraceae). Ann. Missouri Bot. Gard. 69: 1–198.

­­­­­_____. 1985. The systematics of the apetalous Fuchsias of South America, Fuchsia sect. Hemsleyella (Onagraceae). Ann. Missouri Bot. Gard. 72: 213–251.

_____. 1989. A systematic revision of Fuchsia sect. Quelusia (Onagraceae). Ann. Missouri Bot. Gard. 76: 532–584.

Berry, P. E. & D. E. Breedlove. 1996. New taxa of Fuchsia from Central America and Mexico. Novon 6: 135–141.

Berry, P. E., W. J. Hahn, K. J. Sytsma, J. C. Hall, & A. Mast. 2004. Phylogenetic relationships and biogeography of Fuchsia (Onagraceae) based on noncoding nuclear and chloroplast DNA data. Amer. J. Bot. 91: 601–614.

Berry, P. E. & E. Hermsen. 1999. New taxa of Fuchsia (Onagraceae) from northern and central Peru. Novon 9: 479–482.

Berry, P. E., J. J. Skvarla, A. D. Partridge, & M. K. Macphail. 1990. Fuchsia pollen from the Tertiary of Austral. Austral. Syst. Bot. 3: 739–744.

Berry, P. E., B. A. Stein, S. Carlquist, & J. W. Nowicke. 1988. Fuchsia pachyrrhiza, a new tuberous species and section of Fuchsia from northwestern Peru. Syst. Bot. 13: 483–492.

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Bosisio, M. 1990. Squeezing oil from the primrose. Agric. Res. 38: 20–21.

Boufford, D. E. 1982. The systematics and evolution of Circaea (Onagraceae). Ann. Missouri Bot. Gard. 69: 804–994.

____. 2005. Circaea lutetiana sensu lato (Onagraceae) reconsidered. Harvard Pap. Bot. 9: 255–256.

Boufford, D. E., J. V. Crisci, H. Tobe, & P. C. Hoch. 1990. A cladistic analysis of Circaea (Onagraceae). Cladistics 6: 171–182.

Bowman, R. N. & P. C. Hoch. 1979. A new combination in Epilobium (Onagraceae). Ann. Missouri Bot. Gard. 66: 897–898.

Breedlove, D. E. 1969. The systematics of Fuchsia section Encliandra (Onagraceae). Univ. Calif. Publ. Bot. 53: 1–69.

Breedlove, D. E., P. E. Berry, & P. H. Raven. 1982. The Mexican and Central American species of Fuchsia (Onagraceae) except for sect. Encliandra. Ann. Missouri Bot. Gard. 69: 209–234.

Brenan, J. P. M. 1953. Notes on African Onagraceae and Trapaceae. Kew Bull. 8: 163–172.

Brizicky, G. K. 1969. Subgeneric and sectional names: their starting points and early sources. Taxon 18: 643–660.

Bult, C. J. & E. A. Zimmer. 1993. Nuclear ribosomal RNA sequences for inferring tribal relationships within Onagraceae. Syst. Bot. 18: 48–63.

Burnett, G. T. 1835. Outlines of Botany. H. Renshaw, London.

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Candolle, A. P. de. 1828. Onagraceae (as Onagrariae). Prodr. 3: 35–64.

Carlquist, S. 1975. Wood anatomy of Onagraceae, with notes on alternative modes of photosynthate movement in dicotyledon woods. Ann. Missouri Bot. Gard. 62: 386–424.

_____. 1977. Wood anatomy of Onagraceae: additional species and concepts. Ann. Missouri Bot. Gard. 64: 627–637.

_____. 1982. Wood anatomy of Onagraceae: further species; root anatomy; significance of vestured pits and allied structures in dicotyledons. Ann. Missouri Bot. Gard. 69: 755–769.

Carlquist, S. & P. H. Raven. 1966. The systematics and anatomy of Gongylocarpus (Onagraceae). Amer. J. Bot. 53: 378–390.

Carr, B. L., J. V. Crisci, & P. C. Hoch. 1990. A cladistic analysis of the genus Gaura (Onagraceae). Syst. Bot. 15: 454–461.

Carr, B. L., D. P. Gregory, P. H. Raven, & W. Tai. 1986. Experimental hybridization and chromosomal diversity within Gaura sect. Gaura (Onagraceae). Syst. Bot. 11: 98–111.

_____. 1986. Experimental hybridization, chromosomal diversity, and phylogeny within Gaura sect. Stipogaura (Onagraceae). Amer. J. Bot. 73: 1144–1156.

_____. 1988. Experimental hybridization, chromosomal diversity, and phylogeny within Gaura (Onagraceae). Amer. J. Bot. 75: 484–495.

_____. 1988. Experimental hybridization, chromosomal diversity, and phylogeny within Gaura sect. Pterogaura (Onagraceae). Syst. Bot. 13: 324–335.

Casper, B. B. 1990. Seedling establishment from one- and two-seeded fruits of Cryptantha flava: a test of parent-offspring conflict. Amer. Naturalist 136: 167–177.

_____. 1994. Postdispersal sibling competition and the evolution of single-seededness in Cryptantha flava. Evolution 48: 1377–1382.

Chen, C. J., P. C. Hoch, & P. H. Raven. 1992. Systematics of Epilobium (Onagraceae) in China. Syst. Bot. Monogr. 34: 1–209.

Chiu, L. L. & B. B. Sears. 1993. Plastome-genome interactions affect plastid transmission in Oenothera. Genetics 133: 989–997.

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_____. 1972. Oenothera: Cytogenetics and Evolution. Academic Press, London.

Clinebell, R. R., A. Crowe, D. P. Gregory, & P. C. Hoch. 2004. Pollination ecology of Gaura and Calylophus (Onagraceae, tribe Onagreae) in western Texas, U.S.A. Ann. Missouri Bot. Gard. 91: 369–400.

Conti, E., A. Fischbach, & K. J. Sytsma. 1993. Tribal relationships in Onagraceae: implications from rbcL sequence data. Ann. Missouri Bot. Gard. 80: 672–685.

Conti, E., A. Litt, & K.J. Sytsma. 1996. Circumscription of Myrtales and their relationships to other rosids: evidence from rbcL sequence data. Amer. J. Bot. 83: 221–233.

Conti, E., A. Litt, P. G. Wilson, S. A. Graham, B. G. Briggs, L. A. S. Johnson, & K. J. Sytsma. 1997. Interfamilial relationships in Myrtales: molecular phylogeny and patterns of morphological evolution. Syst. Bot. 22: 629–647.

Crisci, J. V. & P. E. Berry. 1990. A phylogenetic reevaluation of the Old World species of Fuchsia (Onagraceae). Ann. Missouri Bot. Gard. 77: 517–522.

Crisci, J. V., E .A. Zimmer, P. C. Hoch, G. B. Johnson, C. Mudd, & N. Pan. 1990. Phylogenetic implications of ribosomal DNA restriction site variation in the plant family Onagraceae. Ann. Missouri Bot. Gard. 77: 523–538.

Dahlgren, R. & R. F. Thorne. 1984. The order Myrtales: circumscription, variation, and relationships. Ann. Missouri Bot. Gard. 71: 633–699.

Delph, L. F. & C. M. Lively. 1989. The evolution of floral color change: pollinator attraction versus physiological constraints in Fuchsia excorticata. Evolution 43: 1252–1262.

Dietrich, W. 1977. The South American species of Oenothera sect. Oenothera (Raimannia, Renneria; Onagraceae). Ann. Missouri Bot. Gard. 64: 425–626.

Dietrich, W., P. H. Raven, & W. L. Wagner. 1985. Revision of Oenothera sect. Oenothera subsect. Emersonia (Onagraceae). Syst. Bot. 10: 29–48.

Dietrich, W. & W.L. Wagner. 1988. Systematics of Oenothera section Oenothera subsection Raimannia and subsection Nutantigemma (Onagraceae). Syst. Bot. Monogr. 24: 1–91.

Dietrich, W., W. L. Wagner, & P. H. Raven. 1997. Systematics of Oenothera sect. Oenothera subsect. Oenothera (Onagraceae). Syst. Bot. Monogr. 50: 1–234.

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_____ . 1840. Oenotheraceae. In Genera Plantarum Secundum Ordines Naturales Disposita, 1188–1195. F. Beck, Vienna.

Evans, M. E. K., D. J. Hearn, W. J. Hahn, J. M. Spangle, & D. L. Venable. 2005. Climate and life-history evolution in evening primroses (Oenothera, Onagraceae): a phylogenetic comparative analysis. Evolution 59: 1914–1927.

Eyde, R. H. 1977. Reproductive structures and evolution in Ludwigia (Onagraceae). I. Androecium, placentation, meristem. Ann. Missouri Bot. Gard. 64: 644–655.

_____. 1979. Reproductive structures and evolution in Ludwigia (Onagraceae). II. Fruit and seed. Ann. Missouri Bot. Gard. 65: 656–675.

_____. 1981. Reproductive structures and evolution in Ludwigia (Onagraceae). III. Vasculature, nectaries, conclusions. Ann. Missouri Bot. Gard. 68: 379–412.

_____. 1982. Evolution and systematics of the Onagraceae: floral anatomy. Ann. Missouri Bot. Gard. 69: 735–747.

Eyde, R. H. & J. T. Morgan. 1973. Floral structure and evolution in Lopezieae (Onagraceae). Amer. J. Bot. 60: 771–787.

Fausto, J. A., Jr., V. M. Eckhart, & M. A. Geber. 2001. Reproductive assurance and evolutionary ecology of self-pollination in Clarkia xantiana (Onagraceae). Amer. J. Bot. 88: 1794–1800.

Fieldsend, A. F. & J. I. L. Morison. 2000. Climatic conditions during seed growth significantly influence oil content and quality in winter and spring evening primrose crops (Oenothera spp.). Industr. Crops Products 12: 137–147.

Ford, V. S. & L. D. Gottlieb. 1999. Molecular characterization of PgiC in a tetraploid plant and its diploid relatives. Evolution 53: 1060–1067.

______. 2003. Reassessment of phylogenetic relationships in Clarkia sect. Sympherica. Amer. J. Bot. 90: 284–292.

_____. 2007. Tribal relationships within Onagraceae inferred from PgiC sequences. Syst. Bot. 32: 348–356.

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