16th International Symposium on Ostracoda (ISO) Brasília, Brazil, July 26-30th 2009

Taxonomy of Permian Ostracoda from Irati and Corumbataí formations in the northern Paraná basin Henrique Z. TOMASSI1 & Dermeval A. DO CARMO1 (1) Universidade de Brasília, Brasília, DF, Brazil. [email protected]

It is presented a taxonomic approach on Permian ostracods from Irati and Corumbataí formations, northern Paraná basin, close to the Araguainha dome, county side of Santa Rita do Araguaia municipality. Herein, eleven ostracod species were recovered: Silenites sp. 1, Silenites? sp. 2, Basslerella sp. 1 Basslerella sp. 2, Saumella? sp. 1, Bairdiacypris sp. 1, Bairdiacypris sp. 2, Langdaia? sp. 1, Gen. 1 sp. 1, Gen. 2 sp. 2 e Gen. 3 sp. 3. All of them are considered marine and do occur in Permian strata. In the past, Corumbataí Formation was considered as Permian-Triassic age, but there are recent articles dating this unity as restricted to Permian. Other authors, considering occurrences in Sucal quarry, date the upper part of it as Triassic. The palaeoenviroment is also a polemic subject, because limnic and marine fossils can be recovered from Irati and Corumbataí formations. In order to solve these polemic questions about the dating and palaeoenvironment, more sections along the basin must be studied.