Pennsylvanian megaspores from northeastern border of the Paraná Basin, Brazil: Correlation with Indian Gondwana megaspores

摘要

Analysis of sediments from Campinas and Monte Mor, municipalities of the State of S?o Paulo, Brazil, has revealed the presence of new megaspores in addition to the known taxa. Trilete, alete, azonate and gulate dispersed fossil megaspores were recorded from the lower and middle levels of the Itararé Group from the northeastern border of the Paraná Basin (Lower Pennsylvanian) of Campinas municipality (Upper Bashkirian - Lower Moscovian) and of Monte Mor municipality (Kazimovian). Twenty-four species of megaspores recovered from one or both of these localities have been systematically analyzed and the synonymy of four previously described megaspores has been discussed. The present study of megaspores from Campinas reveals the presence of the taxa Banksisporites dijkstrae, B. endosporitiferus, B. utkalensis, Biharisporites spinosus, Bokarosporites psilatus, B. rotundus, Duosporites perversus, Duosporites sp. a, Lagenicula horrida, Lagenicula sp., L. nudus, L. rugosus, Lagenoisporites cf. L. hispanicus and Lagenoisporites. sp. The megaspores from Monte Mor includes the taxa Bokarosporites rotundus, Duosporites sp. b, Lagenoisporites nudus, L rugosus and L. cf. L. hispanicus. The taxa Bokarosporites rotundus, B. psilatus, Banksisporites utkalensis, B. endosporitiferus, B. dijkstrae and Biharisporites spinosus are also known from the Permian of India. Banksisporites tenuis previously detected in Campinas and Monte Mor localities is also a species which is shared with India. The presence of these taxa in the Pennsylvanian of the Paraná Basin, Brazil indicates their appearance in the Carboniferous. While all of them persisted up to the Permian, some like Biharisporites spinosus, Banksisporites tenuis and B. utkalensis extend up to Triassic and Early Cretaceous as well. The presence of these megaspores both in India and in Brazil indicates the occurrence of common ancestral heterosporous early land plants. An attempt has been made to interpret the palaeogeographic distribution pattern of some of the megaspores which appeared earlier in Brazil as compared to India, suggesting the floral migration from Brazil towards India.