Pennsylvanian Heteroconchia (Mollusca, Bivalvia) from the Piauí Formation, Parnaíba Basin, Brazil

Abstract

-Dolostones of the upper Piauí Formation, Parnaíba Basin, Northern Brazil, record a rich and diversified invertebrate fauna of the Middle Pennsylvanian (Morrowan to Desmoinesian) age. Among bivalves, Heteroconchia is the most diversified (seventeen species) followed by Pteriomorphia (eleven species) and Palaeotaxodonta (three species Exochorhynchus buriti n. sp.). Adicionalmente, um novo gênero, Carnauba (Megadesmidae), é proposto, sendo representado por espécie única, C. oiticica n. gen. and n. sp. As feições anatômicas internas, diagnósticas de várias espécies, especialmente de Schizodus são descritas pela primeira vez. Finalmente, os bivalves estudados têm afinidades com formas coevas da bacia do Amazonas (Formação Itaituba) e do Carbonífero da América do Norte, reforçando a atribuição de idade Pensilvaniano Médio para a fauna.Palavras-chave: Heteroconchia, Mollusca, Pensilvaniano, Formação Piauí, Brasil.

First occurrence of a lingulide (Brachiopoda: Lingulidae) at Piauí Formation (Upper Carboniferous), Parnaíba Basin, Brazil

“…Among the macroinvertebrates, the bivalve fauna is one of the most diverse of South American upper Paleozoic rocks (Anelli et al, 2009). Gastropods, cephalopods, brachiopods, bryozoans, and trilobites are also present, but in small number (Anelli, 1999;Anelli et al, 2009). Although Campanha & Rocha-Campos (1979) and Anelli et al (2009) mention the occurrence of brachiopods, there is no description or illustration of them.…”

“…Fossils from Piauí Formation, Parnaíba Basin, are known since the early 1940´s and have only recently been studied in more detail (Campanha & Rocha-Campos, 1979;Anelli et al, 2002Anelli et al, , 2006Anelli et al, , 2009Anelli et al, , 2012. Among the microfossils described by Campanha & RochaCampos (1979) are foraminifers, conodonts, bryozoans, ostracods, microgastropods and microbivalves.…”

“…Among the microfossils described by Campanha & RochaCampos (1979) are foraminifers, conodonts, bryozoans, ostracods, microgastropods and microbivalves. Among the macroinvertebrates, the bivalve fauna is one of the most diverse of South American upper Paleozoic rocks (Anelli et al, 2009). Gastropods, cephalopods, brachiopods, bryozoans, and trilobites are also present, but in small number (Anelli, 1999;Anelli et al, 2009).…”

A new Pennsylvanian Oriocrassatellinae from Brazil and the distribution of the genusOriocrassatellain space and time

“…In accordance to this interpretation, Oriocrassatella piauiensis n. sp. from the Piauí Formation is associated with a well diversified warm water fauna (Anelli et al 2002(Anelli et al , 2006(Anelli et al , 2009 González 1972González , 2002 and more rarely in Australia (Runnegar 1972). Also the precursors of the atomodesmids appear to have adapted to warm sea waters, during their migration to the northern hemisphere in the Permian (González & Waterhouse 2012).…”

“…One of the dolostones, informally named Mucambo (Fig. 3A-C), together with other three beds located in the region (see Anelli et al 2006), contains the most diverse bivalve fossil record known from the Upper Paleozoic rocks of South America (Anelli 1999;Anelli et al 2002Anelli et al , 2006Anelli et al , 2009 The Carboniferous and Permian glacial interval in India is just roughly understood from the contributions of Sen (1991), Sen & Banerji (1991) and Maejima et al (2001). It seems that all occurrences known from India are present in rocks deposited after the glacial interval ( Figs 1B, 2[13a-c, 14a]).…”