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Upper Toarcian ostracod assemblages from Boca da Mata, Alvaiázere, Central Portugal, are described to complement earlier work on the ostracods of the Toarcian GSSP at Peniche, western Portugal. A total of 44 species are recorded and the following new taxa described: Cytheropterina ainsworthi sp. nov., Eucytherura alvaiazerensis sp. nov., Otocythere iberobritannica sp. nov., Ophektycythere gen. nov. with O. herrrigi sp. nov., O. mataensis sp. nov. and O.? sicoensis sp. nov. The assemblages reflect oxygenated fully marine, sublittoral shallow water conditions in a proximal margin of the Lusitanian Basin. The species spectrum has most in common with material described from Western Europe especially the Fastnet Basin, offshore Ireland. Lowermost Aalenian assemblages contain some Toarcian species but also new taxa not studied in detail. [ABSTRACT FROM AUTHOR]

This research is focused on the ammonoids of Oxynotum Zone and Raricostatum Zone (Densinodulum Subzone) from Asturian (Spain) and Lusitanian (Portugal) basins. They come from expanded sections from where 216 specimens have been collected. These have been classified in eight genera and 15 species that belong to families Echioceratidae, Oxynoticeratidae and Eoderoceratidae. Most of the ammonoids are typical of the Northwest European Province. Echioceratidae is the most frequent in the Asturian Basin, whereas Oxynoticeratidae is the predominant in the Lusitanian Basin. Eoderoceratidae specimens are scarcer, and they are registered only between the middle part of Oxynotum Subzone and the lower part of Densinodulum Subzone. A new species is proposed for the upper part of Oxynotum Subzone of the Lusitanian Basin, Plesechioceras rochai sp. nov., which is relatively frequent. As well, also in Portugal, Cheltonia sp. is registered in Densinodulum Subzone, which is a form different from Cheltonia accipitris. This provides new evidence to support the hypothesis of the relation micro-macroconch between the genera Oxynoticeras (M) and Cheltonia (m). Remarkable differences in the studied area are the presence of Paroxynoticeras salisburgense and Plesechioceras cf. delicatum in the Asturias Basin, and Crucilobiceras densinodulum, associated to Oxynoticeras lymense, in the Lusitanian Basin. [ABSTRACT FROM AUTHOR]