Growth ring analysis of fossil coniferous woods from early cretaceous of Araripe Basin.

Growth ring analysis on silicified coniferous woods from the Missão Velha Formation (Araripe Basin - Brazil) has yielded important information about periodicity of wood production during the Early Cretaceous in the equatorial belt. Despite warm temperatures, dendrological data indicate that the climate was characterized by cyclical alternation of dry and rainy periods influenced by cyclical precipitations, typical of tropical wet and dry or savanna climate. The abundance of false growth rings can be attributed to both occasional droughts and arthropod damage.

Record of the genus Lycopodites in the Lower Permian of Paraná Basin, Brazil.

The genus Lycopodites, which encompasses the herbaceous forms of the lycopsids, presents broad time and spacial distribution during the Paleozoic in the Northern Hemisphere, with its initial records dating from the European Devonian. As to Gondwanan Paleozoic, to this moment, only Lycopodites amazonica Dolianiti had been reported for the Amazonian Middle Devonian (Curuá Group). Thus, the specimens reported in this study such as Lycopodites sp.

Coricladus quiteriensis gen. et sp. nov., a new conifer in Southern-Brazil Gondwana.

A new taxon of conifers (Coricladus quiteriensis) is described based on megafloristic remains from the roofshale level at the Quiteria Outcrop (Rio Bonito Formation-Lower Permian-Southern Parana Basin-Rio Grande do Sul-Brazil). This megafloristic community is included in the Botrychiopsis Zone--Botrychiopsis valida Sub-Zone (Kungurian/Roadian). The assemblage, preserved as impressions, do not present remains of epidermic characters, and is composed mainly of isolated vegetative branches with spirally disposed acicular leaves, presenting a conspicuous central vein and also isolated fertile branches with sparse and irregular leaves and terminal cones.

The Botrychiopsis genus and its biostratigraphic implications in Southern Paraná Basin.

Botrychiopsis has been considered an important floristic element of Westphalian/Artinskian associations of the Paraná Basin. The occurrence of Botrychiopsis in roof-shales of the Rio Bonito Formation in Southern Paraná Basin (Quitéria area), supported by the identification of Botrychiopsis valida, enlarges the genus biochron. Consequently, the stratigraphic hierarchy for Botrychiopsis plantiana and Botrychiopsis valida was defined for the Paraná Basin.