This study involves bryophyte fossils from the Teresina Formation (Permian-Guadalupian) collected in the Rio Preto Quarry in the state of Paraná, southern Brazil. Two new genera are proposed, with two new species: Capimirinus riopretensis sp. nov. and Yguajemanus yucapirus sp. nov. C. riopretensis sp. nov. included a lateral sporophyte that was organically attached to a gametophyte and is thus one of the oldest pleurocarpous fossils known today. This discovery provides clear evidence of the evolution of mosses during the Permian, because an acrocarpous moss from this period was also found in India. The preservation of such a fragile structure demonstrates that no prefossilization displacement took place and that the sediments accumulated in a low-energy, fresh-water environment, similar to a lake fed by rain, and isolated from the direct influence of the sea. Campimirinus riopretensis may be placed within the earlier pleurocarps, and Yguajemanus yucapirus sp. nov. may belong to the Bryalean families. However, we were not able to place neither of these species in any existing family today.
This paper introduces a methodology which makes possible the visualization of the spatial distribution of plant fossils and applies it to the occurrences of the Gondwana Floristic Province present on the eastern border of the Brazilian portion of the Paraná Basin during the Neopaleozoic. This province was chosen due to the existence of a large number of publications referring to their occurrence, so that a meta-analysis of their distribution could be based on ample information. The first step was the construction of a composite database including geographical location, geology, and the botanical systematics of each relevant fossil. The geographical locations were then georeferenced for translation into various maps showing various aspects of the distribution of the fossils. The spatial distribution of the fossil-housing outcrops shows that these are distributed along the area of deposition studied. Although some genera persisted for long periods of time, others lasted for only short intervals. As time passed, the fossil composition underwent a gradual change from the Late Carboniferous (Itararé Group) to the Late Permian (Rio do Rasto Formation), with the number of genera represented decreasing from 45 in the Itararé Group to 11 in the Rio do Rasto Formation. KEYWORDS:Geographic Information Systems; Gondwana Floristic Province; Paraná Basin; Floristic Maps. RESUMO: O presente artigo introduz a uma metodologia na qual será possível a visualização da distribuição espacial de fitofósseis. Tal metodologia será aplicada a ocorrências da Província Florística do Gondwana presente na borda leste da porção brasileira da Bacia do Paraná durante o Neopaleozóico. Essa província foi escolhida tendo em vista que nela há grande número de publicações referentes às suas ocorrências. Isso torna possível a meta-análise de sua distribuição
Fossil bryophytes are rare because their preservation is compromised by the presence of a thin cuticle (if any) and a lack of lignin. Except for the occurrence of one bryophyte in the glacial Dwyka Group of the Karoo Basin, the other rare Late Paleozoic records in Gondwana are notably from the Paran a Basin in Southeast/South Brazil. Four bryophyte sites (including a newly discovered one) were found in the lower part of the thick Permo-Carboniferous glacial succession of the Itarar e Group, and one was found in the Guadalupian Teresina Formation, which was roughly assigned to an epeiric sea (or "lake") dominated by a warm, semi-arid climate. This study describes the fossils from the new occurrence from the Itarar e Group and discusses the context in which the bryophyte beds originated in the basin. The new samples confirm that all of the bryophytes of the Itarar e Group can be classified as Dwykea araroii Ricardi-Branco et al. (a possible pleurocarp) and are associated with the lycophyte megaspore Sublagenicula brasiliensis (Dijkstra) Dybov a-Jachowicz. In the much younger Teresina Formation, the bryophytes are Yguajemanus yucapirus Cristiano-de-Souza et al. and Capimirinus riopretensis Cristiano-de-Souza et al., and abundant charophytes and rare dwarf lycophyte stems and bracts are present in the same layers. Although the two stratigraphic units represent distinct paleoenvironments and climates, they seem to share some characteristics: a) the bryophyte assemblages were transported very little; b) they were deposited in very calm environments; c) they were the main components (along with some lycophytes) of local or poorly diversified regional vegetation. The low number of species, which is characteristic of opportunistic communities, can be explained by local or regional conditions that would have been stressful for the vascular plants in other areas. During the deposition of the Itarar e Group, the main control was probably the cold climate in addition to a relative (liquid) water deficit because the bryophyte vegetation may have belonged to a tundra biome in areas of retreating glaciers. For the Teresina Formation, it is possible that the control was scarce freshwater, an unstable environment and water-saturated soil in a scenario of bryophyte vegetation living around temporary ponds in a wide marginal area of the epeiric sea.
Leonardosia Sommer is one of the scarce Permian charophyte genera and is part of the lineage that may include the ancestors of the post-Palaeozoic families. Oospores of the species Leonardosia langei Sommer have been found in strata of the Teresina Formation, Paraná Basin, Southern Brazil, where they are preserved as compressions. The charophyte organs found in this formation, including the original description of Leonardosia have been previously been interpreted as gyrogonites despite the presence of a carbonaceous film. We propose that these charophyte organs and the fructifications should be re-interpreted as organic oospores rather than gyrogonites. The coiling pattern, in most cases, proved to be reverse as a result of the compres-sion of the oospore against the internal wall of the dissolved gyrogonite. In some cases, the coiling was ambiguously observed in both directions by an overlap of the opposite walls of the oospore and the dissolved gyrogonite. A simple basal plate for L. langei was registered, and its relation with the main ideas about the phylogeny and the evolution of Mesozoic charophytes is also discussed. The 'Stellatocharoideae' is polyphyletic including both the stem lineage of the Nitellaceae, represented by the multipartite basal plate genera, and a clade that belongs to the evolutionary line of the Monoplacata, represented by Leonardosia.
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