Runcaria, a Middle Devonian Seed Plant Precursor

@article{Gerrienne2004RuncariaAM,
  title={Runcaria, a Middle Devonian Seed Plant Precursor},
  author={Philippe Gerrienne and Brigitte Meyer-Berthaud and Muriel Fairon‐Demaret and Maurice Streel and Philippe Steemans},
  journal={Science},
  year={2004},
  volume={306},
  pages={856 - 858}
}
The emergence of the seed habit in the Middle Paleozoic was a decisive evolutionary breakthrough. Today, seed plants are the most successful plant lineage, with more than 250,000 living species. We have identified a middle Givetian (385 million years ago) seed precursor from Belgium predating the earliest seeds by about 20 million years. Runcaria is a small, radially symmetrical, integumented megasporangium surrounded by a cupule. The megasporangium bears an unopened distal extension protruding… Expand
The significance of Runcaria (Middle Devonian, Belgium) in the evolution of seed plants
TLDR
A suite of characters observed in the Late Devonian preovules Moresnetia and Elkinsia and in a number of younger taxa define hydrasperman reproduction, and the possession of a massive nucellar tip and the lack of pollen chamber characterized another primitive seed organization that either preceded and was ancestral to the hydr Jasperman type, or evolved independently and was adaptated to wet habitats. Expand
Early seed plant radiation: an ecological hypothesis
Abstract The earliest steps of seed plant evolution have been extensively studied during the past 25 years. There is a growing body of evidence indicating that the first major spermatophyte radiationExpand
Early diversification of seeds and seed-like structures
TLDR
The seed habit involves occurrence of a single functional megaspore within an indehiscent megasporangium (nucellus), development of an endosporic megagametophyte, enclosure of the nucellus by an integument, and capture of pollen before dispersal from the sporophyte. Expand
Letters to the twenty-first century botanist. Second series: “what is a seed?” – 3. How did we get there? Palaeobotany sheds light on the emergence of seed
TLDR
The main steps leading to the acquisition, during the Palaeozoic, of the seed habit are discussed, and the earliest seeds containing embryos are reported in Carboniferous coniferophytes. Expand
Seed coat thickness in the evolution of angiosperms
TLDR
The great natural diversity observed in seed coat thickness among angiosperms and its molecular regulation in Arabidopsis is reviewed. Expand
A Middle Devonian Callixylon (Archaeopteridales) from Ronquières, Belgium
article i nfo A permineralized Callixylon trunk is reported from Ronquieres, a mid to late Givetian (Middle Devonian) locality from Belgium. The specimen consists of an 80 cm long trunk adpressionExpand
Diversity of Mississippian Arborescent Lignophytes: A New Species of Eristophyton from the Middle Tournaisian of France
Decorticated woody stems from the Tournaisian (early Mississippian) of Montagne Noire, Southern France, are characterized by a wide eustele with a parenchymatous pith and numerous primary xylemExpand
Cosmosperma polyloba gen. et sp. nov., a seed plant from the Upper Devonian of South China
TLDR
Cosmosperma Wang et al. represents the first Devonian ovules recovered from China or eastern Asia and further illustrates the diversity of early spermatophytes. Expand
L’évolution des premiers arbres : les stratégies dévoniennes
TLDR
The earliest axes exceeding 10 cm in diameter, and presumed to represent small trees, evolved in the Middle Devonian (about 395 million years), and are characterized by a symmetrical development of the aerial and underground parts that branch dichotomously. Expand
Omniastrobus gen. nov., an Emsian Plant with Implications for the Evolution of Heterospory in the Early Devonian
Premise of research. Heterospory, or the production of different spore size classes, is a key aspect of advanced vascular plant reproductive strategies. Heterospory is widespread across plantExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 18 REFERENCES
A Mid Devonian seed-megaspore from East Greenland and the origin of the seed plants
TLDR
Ulastructural study of the megaspore wall confirms the progymnosperm affinity of S. allenii and provides a more likely mechanism for seed plant origin than the archaeopteridalean sporangium reduction model. Expand
A primitive seed-like structure and its implications for early gymnosperm evolution
TLDR
The unique anatomically preserved seed-like structure found in the early Carboniferous, Montagne Noire, France, shows the unequivocal absence of a pollen chamber indicating a more primitive organization than that known from any other late Devonian or early carboniferous seed. Expand
New dispersed seed-megaspores from the mid-Givetian of European Russia
TLDR
A new genus and species of dispersed megaspore tetrads, consisting of one large and three small spores, are described from mid-Givetian deposits of European Russia, probably the oldest seed-megaspores recorded so far. Expand
ORIGIN OF SEED PLANTS: AN ANEUROPHYTE/SEED-FERN LINK ELABORATED'
TLDR
Gymnosperm-like stem and frond fragments have been discovered in the same Devonian deposits of West Virginia that yield the most ancient seeds, which supports the hypothesis that aneurophytalean progymnosperms are ancestral to gymnosperms. Expand
Frasnian (Upper Devonian) evidence for multiple origins of seed-like structures
TLDR
Reproductive structures of Frasnian (early Late Devonian) age from Wuhan, Hubei province, South China provide evidence for the early emergence of monomegaspory and integumentation in plants of non-progymnosperm affinity and demonstrates that the Devonian progymnosperms did not lack potential competition from similarly specialized reproductive strategies in other plant lineages. Expand
First Devonian platyspermic seed and its implications in gymnosperm evolution
IN the course of an investigation of fossil plants from the late Devonian rocks of Kiltorcan in southern Ireland obtained by re-excavation of the site earlier this year, we have discovered severalExpand
Dorinnotheca streelii Fairon-Demaret, gen. et sp. nov., a new early seed plant from the upper Famennian of Belgium
TLDR
This new early seed plant bears cupules hanging singly at the tips of the slender ultimate axes of a pinnately branched system, which is described from three upper Famennian localities in Belgium. Expand
ORIGINS OF HETEROSPORY AND THE SEED HABIT: THE ROLE OF HETEROCHRONY
Summary The origin of the seed-plant life history, and subsequent diversification of seed morphology, should be considered two independent, fundamentally distinct evolutionary problems. GametophyticExpand
A new Late Devonian acupulate preovule from the Taff Gorge, South Wales
TLDR
In the absence of earlier records of seed plants and of information on the morphology and anatomy of entire plants, it is impossible to determine whether the new preovules were part of the initial phase in seed-plant radiations from a common ancestor or whether they provide evidence for a polyphyletic origin for the gymnosperms. Expand
Elkinsia gen. nov., a Late Devonian Gymnosperm with Cupulate Ovules
An extensive collection of fossilized ovules, ovulate cupules, and cupuliferous branching systems from late Devonian deposits of eastern West Virginia is described and named Elkinsia polymorpha gen.Expand
...
1
2
...