Silurian Trilete Spores and Spore Tetrads from Gotland: Their Implications for Land Plant Evolution

  title={Silurian Trilete Spores and Spore Tetrads from Gotland: Their Implications for Land Plant Evolution},
  author={Jane Gray and Sven Laufeld and Arthur James Boucot},
  pages={260 - 263}
Land-plant type spores occur in argillaceous limestones and platform graptolitic mudstones of Wenlock-Ludlow age in Sweden. Analysis of the stratal sequence demonstrates that occurrence of abundant spores is a function of depositional ecology, particularly water depth and shoreline proximity. This ecological analysis and the seeming absence of any correlation between the first appearances of abundant spores and megafossils of land-plant type raise the possibility that land plants evolved far… 

The distribution of trilete spores in Irish Silurian rocks

  • D. Smith
  • Geology, Environmental Science
    Geological Society, London, Special Publications
  • 1979
Summary Trilete spores of land-plant type have been recovered from probable late Llandovery to early Ludlow sediments in several widespread parts of Ireland, and they have proved to be

Upper Silurian trilete spores and other microfossils from the Read Bay Formation, Cornwallis Island, Canadian Arctic

A diverse palynomorph assemblage of trilete spores, tetrads, acritarchs, chitinozoans, scolecodonts, and fragments of arthropods, ?hydrozoans, ?graptolites, and possibly nematophytalean and vascular

The oldest vascular land plants: A note of caution

Silurian fungal remains: probable records of the Class Ascomycetes

It is suggested that these microfossils obtained from the late Silurian Burgsvik Sandstone represent the remains of the imperfect stages of terrestrial Ascomycetes, and provide evidence for an origin of this group at least contemporaneous with the earliest land plants.

Fragmentary non‐vascular plant microfossils from the late Silurian of Wales

It is concluded that the majority of these microfossils derive from non-vascular plants of uncertain affinity which lived on land.

Wenlock plant spores and tetrads from County Mayo, Ireland

Summary A rock sample from the Lettergesh Formation, most probably from the centrifugus Zone of the early Wenlock on graptolite evidence, has yielded microfossils including spores, most of which

Late Ordovician (Katian) spores in Sweden: oldest land plant remains from Baltica

A palynological study of the Ordovician–Silurian boundary (Katian–Rhuddanian) succession in the Röstånga-1 drillcore, southern Sweden, has been performed. The lithology is dominated by mudstone and

The spore record of early land plants from upper Silurian strata in Klinta 1 well, Skåne, Sweden

Samples from the upper Silurian Oved-Ramsasa Group, Skane, Sweden have been investigated palynologically. The sediments are dominated by siliciclastic deposits with minor carbonate units and the

Devonian thalloid plants (Orestoviaceae) and associated spore tetrads

It is suggested that Schuguria and Orestovia represent sexual and asexual generations of a nearly isomorphic reproductive cycle and the tetrads might have been produced by a sporophytic member of the Orestoviaceae.

Plant microfossils from Llandoverian and Wenlockian rocks of Pennsylvania

Abstract Macerations of greenish shales from the Tuscarora Formation (Llandoverian) and Clinton? strata (Wenlockian) in central and eastern Pennsylvania yield a remarkable assemblage of spores and



Early Silurian Spore Tetrads from New York: Earliest New World Evidence for Vascular Plants?

P Paleoecological evidence suggests that these spores may represent vascular land or semiaquatic plants but a bryophytic origin cannot be precluded on the basis of spore characters, and an algal origin is considered unlikely.

Silurian palynomorphs from the Tanezzuft and Acacus formations, Tripolitania, North Africa

50 miospore forms described (four new species), acritarchs figured, assemblages compared to North American and European, post-Llandoverian to pre-Downtonian; Libya

Palynological Evidence Bearing on the Ordovician-Silurian Paraconformity in Ohio

Organic microfossils (spore tetrads, acrit-archs, scolecodonts, chitinozoans) from six Late Ordovician through Early Silurian samples (Elkhorn Formation of the Richmond Group; lower and upper beds of

On the Plant-Remains from the Downtonian of England and Wales

The strata from which the plant-remains to be described in this paper are derived are those which are grouped as Downtonian in the extended sense of this term employed by Mr. W. Wickham King. They

Table 1) were provided by S.L., who had previously noted resistant spores in a number of his Gotland chitinozoan preparations

  • Forty-three fresh rock aliquots from localities in Gotland and Scania (Fig. 1

Older trilete spores and spore tetrads are reported in

  • 1959

Fossils Strata, in press

  • Palaeontol. Abh. 120,
  • 1964

although their botanical affinities remain in considerable doubt [see B. Lundblad

  • Common fossil remains attributed to land vascular plants have been described from Gotland
  • 1920