PENNSYLVANIAN HETEROCONCHIA (MOLLUSCA, BIVALVIA) FROM THE PIAUI FORMATION, PARNAIBA BASIN, BRAZIL

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pennsylvanian Pteriomorphian bivalves from the Piaui Formation, Parnaiba Basin, Brazil

Dolostones of the upper Piaui Formation, Parnaiba Basin, northern Brazil, preserve a rich and diversified invertebrate fauna of Morrowan to Desmoinesian age. Among bivalves, Heteroconchia (15 species) is the most diversified, followed by Pteriomorphia (11 species), and rare endobenthic species of the Palaeotaxodonta. (three species). Eleven species of Pteriomorphia are described, including representatives of the genera Parallelodon?, Myalina?, Septimyalina, Caneyella?, Leptodesma (Leptodesma), L. (Leiopteria), Meekopinna?, Aviculopinna?, and Aviculopecten. A new combination, Etheripecten trichotomus, and the oldest member of the Anomiidae recorded, Pindorama nordestina n. gen. and sp., also are described. Details of muscle scars and hinge characters have been recovered for several taxa, thereby refining the knowledge for species diagnoses. Fossil beds in the Esperanca and Mucambo dolostones reveal episodic burial of bivalves in life position. These are internally complex, multistory fossil concentrations recording background and episodic processes. Hence, those fossil concentrations show high degrees of time-averaging and poor palcoecological resolution (except for the bivalves preserved in situ).

A new Pennsylvanian Oriocrassatellinae from Brazil and the distribution of the genus Oriocrassatella in space and time

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Biostratigraphy and paleoecology of an unusual palynological record from the Aquidauana Formation, Late Pennsylvanian of Paraná Basin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)