Record of Glossopterid Plants in the Southern Region of Brazil

We summarize here the glossopterid record for the late Paleozoic of southernmost Paraná Basin from the Kazimovian – Gzhelian through the Roadian, a time interval spanning ca. 30 Ma. Isolated and clustered leaves are the dominant fossils; reproductive organs, conductive tissues (Agathoxylon-type wood), and Vertebraria roots were less frequently described. The material is mostly preserved as impressions, very rarely as petrifactions or compressions. The oldest leaf patterns within the studied interval show the dominance of the Gangamopteris over Glossopteris during the final stages of deglaciation (307.7 ± 3.1 Ma) and the increasing dominance of Glossopteris during the early Permian peat-deposition cold temperate interval (295.8 ± 3.1–304.0 ± 5.6 to 285.42 + 1.2/−2.1 Ma), when the glossopterids reached their acme under low CO2 paleoatmospheric levels. The conservative morphography of the leaves in almost all the studied intervals contrasts with distinct patterns of ovuliferous structures related to the genera Arberia, Ottokaria, and Plumsteadia. The persistence of Glossopteris as a component of floristic associations in the Kungurian and Roadian after the disappearance of environmental and climatic conditions favorable to the development of extensive peatlands during the Asselian–Artinskian interval attests to the remarkable adaptative capacity of these plants.