Mesozoic cupules and the origin of the angiosperm second integument.

@article{Shi2021MesozoicCA,
  title={Mesozoic cupules and the origin of the angiosperm second integument.},
  author={Gongle Shi and Fabiany Herrera and Patrick S. Herendeen and Elizabeth G. Clark and Peter R. Crane},
  journal={Nature},
  year={2021}
}
The second integument of the angiosperm ovule is unique among seed plants, with developmental genetics that are distinct from those of the inner integument1. Understanding how the second integument should be compared to structures in other seed plants is therefore crucial to resolving the long-standing question of the origin of angiosperms2-6. Attention has focused on several extinct plants with recurved cupules that are reminiscent of the anatropous organization of the basic bitegmic ovules of… 

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References

SHOWING 1-10 OF 19 REFERENCES

Angiosperm ovules: diversity, development, evolution.

The present review provides a synthetic treatment of several aspects of the sporophytic part of ovule diversity, development and evolution, based on extensive research on the vast original literature and on experience from my own comparative studies in a broad range of angiosperm clades.

Anatomy of umkomasia (corystospermales) from the triassic of antarctica.

Both anatomical and morphological features support interpretation of corystosperm reproductive structures as branching systems rather than as compound sporophylls.

Integrating Molecular Phylogenetic and Paleobotanical Evidence on Origin of the Flower

  • J. Doyle
  • Biology
    International Journal of Plant Sciences
  • 2008
Results and developmental genetic data are consistent with homology of the angiosperm bitegmic ovule with the cupule of glossopterids and Caytonia, while the carpel could represent a leaf and a cupule‐bearing axillary branch in living basal angiosperms.

Origin of Angiosperms

In the apparent absence of critical fossil evidence, ideas on the origin of angios­ perms have been based largely on comparative morphology of modern plants, including Axelrod's theory that the angiosperms originated and began to diversify extensively in tropical upland areas as early as the Permian or Triassic.

After a dozen years of progress the origin of angiosperms is still a great mystery

The ‘anthophyte theory’, the dominant concept of the 1980s and 1990s, has been eclipsed; Gnetales, previously thought to be closest to the angiosperms, are related instead to other extant gymnos perms, probably most closely to conifers.

Diversity and homologies of corystosperm seed-bearing structures from the Early Cretaceous of Mongolia

The consistent reproductive architecture of the seed-bearing structures in all three corystosperm species, with a bract subtending a variously modified axis bearing ovules, is similar to the situation in Ginkgo and conifers.

Habit and Ecology of the Petriellales, an Unusual Group of Seed Plants from the Triassic of Gondwana

The hitherto enigmatic Petriellales are now among the most comprehensively reconstructed groups of extinct seed plants and emerge as promising candidates for elucidating the mysterious origin of the angiosperm carpel.

Geminispermum, an Early Cretaceous (early–middle Albian) cupulate unit from the angiosperm-dominated Puddledock flora of eastern North America

Geminispermum is currently the only unequivocal seed plant cupule recovered from the Early Cretaceous Potomac Group and is distinct from all previously described cupulate reproductive structures.

New perspectives on the Mesozoic seed fern order Corystospermales based on attached organs from the Triassic of Antarctica.

Phylogenetic analysis suggests that the corystosperm cupule is an unlikely homologue for the angiosperm carpel or outer integument, and studies that treat Dicroidium leaf morphospecies as proxies for biological species of entire plants should be reconsidered.

Phylogenetic diversification of Early Cretaceous seed plants: The compound seed cone of Doylea tetrahedrasperma.

The unique combination of characters shown by D. tetrahedrasperma includes the presence of cupulate seeds borne in conifer-like compound seed cones, an ovuliferous scale analogue structurally equivalent to the ovulate stalk of Ginkgo biloba, gymnospermous pollination, and nearly complete enclosure of mature seeds.