Saturday, May 17, 2014

[Paleontology • 2014] The Cretaceous (Cenomanian) continental record of the Laje do Coringa flagstone (Alcântara Formation), Brazil, northeastern South America


Fig. 4. On land: sauropod titanosaurids (left) and andesaurids (right); theropod spinosaurid (center) and noasaurid (right); sawfish Atlanticopristis equatorialis. Flying: Anhangueridae.
In the water: left – Mawsonia gigas (close to the surface), Pycnodontiform (middle) Myliobatis sp. (botton); right – Tribodus sp. (sharks), Lepidotes sp. (up), ceratodontid (middle), and the sawfish Onchopristis sp. (background).
illustration: Rodolfo Nogueira 

Highlights
• A summary of the Cretaceous flora and fauna of Alcântara Formation, Brazil.
• Evidence of the existence of a trans-oceanic Gondwanan fauna until the Cenomanian.
• Forested areas surrounded by dry environment in Brazilian northeastern coast.

Abstract
The fossil taxa of the Cenomanian continental flora and fauna of São Luís Basin are observed primarily in the bone bed of the Laje do Coringa, Alcântara Formation. Many of the disarticulated fish and tetrapod skeletal and dental elements are remarkably similar to the chronocorrelate fauna of Northern Africa. In this study, we present a summary of the continental flora and fauna of the Laje do Coringa bone-bed. The record emphasizes the existence of a trans-oceanic typical fauna, at least until the early Cenomanian, which may be interpreted as minor evolutionary changes after a major vicariant event or as a result of a land bridge across the equatorial Atlantic Ocean, thereby allowing interchanges between South America and Africa. The paleoenvironmental conditions in the northern Maranhão State coast during that time were inferred as forested humid areas surrounded by an arid to semi-arid landscape.

Keywords: Alcântara Formation; São Luís Basin; Cretaceous; Cenomanian


Manuel Alfredo Medeiros, Rafael Matos Lindoso, Ighor Dienes Mendes and Ismar de Souza Carvalho. 2014. The Cretaceous (Cenomanian) continental record of the Laje do Coringa flagstone (Alcântara Formation), northeastern South America. Journal of South American Earth Sciences. 53, 50–58. dx.doi.org/10.1016/j.jsames.2014.04.002

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