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The fossiliferous marine Miocene sediments of the Lower Tagus Basin (Portugal) present a great diversity of Chondrichthyes forms. The current study focuses on the fossil sharks from the Langhian Vc unit of the Brielas section, located in the Setúbal Peninsula. A total of 384 isolated fossil teeth were analysed and ascribed to 17 species from the Orders Hexanchiformes, Squaliformes, Squatiniformes, Lamniformes, and Carcharhiniformes. Centrophorus granulosus and Iago angustidens are described for the first time in Portuguese sediments, whereas Pachyscyllium dachiardii and Rhizoprionodon ficheuri represent only their second reported occurrence. Galeorhinus goncalvesi was already known from the Portuguese uppermost Miocene (Alvalade Basin), but it is now recognized in older sediments. Furthermore, the new material seems to include the first reported occurrence of Hexanchus cf. agassizi in Miocene sediments. As a whole, these new findings support the previous palaeoenvironment characterization of a warm infralittoral setting gradually deepening to a circalittoral one, where seasonal upwelling phenomena could have occurred. [ABSTRACT FROM AUTHOR]

The Langhian Vc unit of Brielas section (Caparica road, Almada), in the marine Miocene of the Lower Tagus Basin (West Portugal), is rich in batoid species. In this study, batoids are represented by 149 isolated fossil teeth and a single fossil dental plate collected from a bulk sample of washed and sorted sediment. A total of 12 species belonging to the orders Rhinopristiformes, Rajiformes, Torpediniformes and Myliobatiformes were identified. All genera and some species are known to have extant representatives. Aetobatus cappettai antunes and balbino, 2006, is described now from Langhian material which suggests it is older than previously supposed. The biogeographic ranges, environmental constraints and behaviour of the species described in this study point out to an infralittoral environment characterized by the dominance of warm water conditions, where episodic upwelling contributed to the occurrence of different types of batoids coexisting in the same habitat. [ABSTRACT FROM AUTHOR]

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Abstract: Rajiformes teeth from the Esbarrondadoiro Formation, Latest Miocene from the Alvalade basin are described. These teeth have been ascribed to the following genera: Rhynchobatus, represented by Rhynchobatus pristinus; Rhinobatos, by Rhinobatos sp.; and Raja, by Raja olisiponensis and Raja sp. Taxonomic distribution among localities is quantitatively different, which is related to different paleoenvironmental conditions. [Copyright &y& Elsevier]

Abstract: This paper deals with the only latest Miocene fish fauna so far recognized in Portugal and probably in western Europe through more than 10,000 teeth and many other remnants collected in the Latest Miocene, Esbarrondadoiro Formation (Alvalade basin, southern Portugal). A large number of teeth reported to the family Dasyatidae (ca. 46% among the Myliobatiforms) are described. Several forms were recognized. The concerned deposits are particularly rich in modern type, close to still extant selachian forms. This is confirmed by the presence of different species of Dasyatis. From the thermic point of view, Alvalade basin marine fishes point out to a decrease in the prevailing thermic conditions. The still abundant Dasyatis are in contrast to the rarity of Raja, a genus which suggests temperate or cold, or deeper hence colder waters. Moderately warm water conditions predominated, less than in Tortonian of Lisbon, more than exist today near the Portuguese coasts. The occurrence ratios of the taxa concerned among the exploited sites are quantitatively different. This points out to different paleoenvironmental conditions. The Dasyatis had a litoral/neritic bathymetric distribution and a benthic way of life. However, the Esbarrondadoiro pattern is very different from those from Santa Margarida and Vale de Zebro, which are nearly identical between them as far as Dasyatis gr. gigas and Dasyatis sp. are concerned: Dasyatis gr. gigas may suggest less warm waters, and this is very much compatible with other data that indicate a deeper environment and hence colder waters for Esbarrondadoiro. [Copyright &y& Elsevier]

Abstract: Portuguese meaningful contributions to the Natural History of territories under the rule or influence of Portugal since the 16th century have most often been despised or just ignored. This is the case of the discovery by a Portuguese naturalist of the remarkable Cretaceous fossil fish localities from Ceará. The collecting of such fossils could be ascribed to the end of 18th century. Fossiliferous nodules have indeed been received in Lisbon well before 1807. Some have been rediscovered among the old collections of the Lisbon Academy of Sciences. Their origin may certainly be ascribed to the Santana Formation in Ceará. Additional evidence consists of a letter/report by João da Sylva Feijoo, a Rio de Janeiro-born naturalist that got his degree at the Coimbra University. This letter is dated “Siara 11 de Dezembro de 1800”. This document remained almost unknown, even if it has been published. Feijoo is better known as leader of a mission to Cape Verde archipelago, where he had been sent by the Portuguese government. He returned to Lisbon, where the Academy of Sciences published some memoirs by him. Sometime later, Feijoo returned to Brazil and settled down in Ceará, where he carried on prospecting work. Feijoo (ibid.) dealt with the saltpetre mine at Sítio Tatajuba and mentions that he sent samples from there to Lisbon for analyses. The corresponding samples have been sent to the Governor as well as fossil fishes. He also provides some discussion on the latter''s occurrence conditions and expressed his wish to prepare a more detailed memoir on these fossil fishes. This is accordingly the origin of the nodules of the Lisbon Academy''s Museum, where these specimens have probably been transferred from the Ajuda Royal Museum in Lisbon. As a concluding remark, let us say that, in our present state of knowledge, the first discovery of (and the first report on) the famous Cretaceous fishes from Ceará have indeed been that by the Portuguese citizen, the naturalist João da Sylva Feijoo, well before the supposedly, often claimed first discovery that has been related to the well-known expedition by Spix and Martius. To cite this article: M. Telles Antunes, C. R. Palevol 4 (2005) . [Copyright &y& Elsevier]