Archaefructus
Archaefructus is an extinct genus of herbaceous aquatic seed plants. Its fossils come from the Yixian Formation in northeastern China, about 125 million years ago in the early Cretaceous. Archaefructus is the earliest known genus of flowering plants.[1]
| Archaefructus Temporal range: Early Cretaceous
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| Archaefructus liaoningensis - a photograph of a facsimile of the fossil | |
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| Family: | Archaefructaceae |
| Genus: | Archaefructus |
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Archaefructus eoflora | |
It lacks sepals and petals. Its reproductive organs, carpels and stamens, are produced on an elongate stem rather than condensed into a flower as in modern angiosperms. Archaefructaceae has been proposed as a new basal angiosperm family.[1]
An alternate interpretation of the same fossil has the long stem as an inflorescence rather than a flower, with staminate (male) flowers below and pistillate (female) flower above.[2] The discovery of Archaefructus eoflora supports this interpretation,[3] because a bisexual flower is present between staminate and pistillate organs. If this is correct, Archaefructus may not be basal within angiosperms, but it may be close to the Nymphaeales or the basal eudicots.
References
- ↑ 1.0 1.1 Sun G. et al 2002. Archaefructaceae, a new basal Angiosperm family. Science 296(5569): 899–904.
- ↑ Friis E.M. et al 2003. Archaefructus – Angiosperm precursor or specialized early angiosperm? Trends in Plant Sciences 8: 369–373.
- ↑ Ji Q. et al 2004. Early Cretaceous Archaefructus eoflora sp. nov. with bisexual flowers from Beipiao, Western Liaoning, China.PDF (3.11 MiB) Acta Geologica Sinica 78(4): 883–896.