Abstract The Neogene benthic foraminiferal ecostratigraphy of offshore Pelotas Basin has not yet been researched. The benthic foraminifera were examined in twenty-nine ditch cuttings samples from Well 1-SCS-3B, present water depth 200 m. These samples ranged from the Lower Miocene Catapsydrax dissimilis planktonic foraminiferal Zone to the Pliocene Globigerinoides trilobus fistulosus Zone. Only ditch cuttings were available, which allowed us to present just broad paleoenvironmental trends within the studied section. Benthic foraminifera indicate deposition mostly between outer neritic to upper bathyal paleodepths. A peak in uvigerinid relative abundance marks a possible flooding surface or condensed section with a high nutrient flux, low diversity (marked by the Shannon Function H), and sluggish circulation within the Globorotalia mayeri Zone. This peak is bracketed by high abundances of Cibicidoides, which indicate stronger current action than within the condensed section. Biostratigraphic hiatuses within these Cibicidoides-rich intervals are concluded not to indicate subaerial exposure, but to reflect current action sufficiently strong to induce either non-deposition or seafloor scouring. A second possible flooding surface occurs at the top of the section, indicated by a decline in Cibicidoides associated with upticks in Sphaeroidina and Bolivina and a dip in H. The top of this younger maximum flood was not encountered, probably occurring above the studied section. That the timing of these floods differs from those recorded elsewhere in the Pelotas Basin implies that they were tectonically induced, perhaps as distal effects associated with the interaction between the South American and Nazca tectonic plates. Future studies with better quality core samples will add detail to this picture; such studies can incorporate eustatic sea-level changes into the model presented.

Duas novas espécies de Xestoleberididae: Xestoleberis brasilinsularis sp. nov. e Xestoleberis machadoae sp. nov., ambas endêmicas do Arquipélago São Pedro e São Paulo, são descritas. O registro dessas espécies marinhas de águas rasas em ilhas oceânicas brasileiras representa uma importante contribuição para o conhecimento da história evolutiva das espécies que habitam estas áreas.

Two new species of Xestoleberididae: Xestoleberis brasilinsularis sp. nov. and Xestoleberis machadoae sp. nov., both endemic to Archipelago of São Pedro and São Paulo, are described. The record of these shallow marine waters species from Brazilian oceanic islands represents an important contribution to the knowledge of the evolutionary history the species inhabit areas.

Foram coletadas 62 amostras de sedimentos de fundo e fital no infralitoral rochoso superior (< 3 m de profundidade) das regiões central e norte do Estado de Santa Catarina (26º10'/27º50'S – 48º26'/48º40'W). Os ostracodes vivos e mortos recuperados estão distribuídos em 16 famílias, destacando-se, neste trabalho, um novo gênero e espécie de Hemicytheridae ricamente descrito e ilustrado: Auricythere sublitoralis gen. nov., sp. nov. Alguns aspectos ecológicos e zoogeográficos deste novo táxon são brevemente discutidos.

This study is based on 62 samples of phytal and bottom sediments collected along rocky beaches (< 3 m water depth) of the central and northern coasts of the state of Santa Catarina (26º10'/27º50'S – 48º26'/48º40'W), southern Brazil. Living and dead ostracodes distributed among 16 families were recovered. In this paper is emphasized one new hemicytherid genus and species that is described and richly illustrated: Auricythere sublitoralis gen. nov. and sp. nov. Some ecological and zoogeographical aspects of this new ostracode are briefly discussed.

O presente estudo é uma contribuição para o conhecimento da sistemática dos ostracodes marinhos rasos das ilhas oceânicas brasileiras. Um total de 14 espécies pertencentes a 10 gêneros e oito famílias é aqui identificado. Um novo gênero e espécie são descritos e ilustrados: Berguecythere insularis gen. nov., sp. nov. Além desse novo táxon, foram também identificados Loxocorniculum tricornatum Krutak, 1971, espécie abundante amplamente distribuída em sedimentos recentes do Golfo do México, Caribe, norte e nordeste do Brasil e no Atol das Rocas, e o ostracode cosmopolita tropical Triebelina sertata Triebel, 1948. As 11 espécies restantes foram deixadas em nível de gênero e devem fornecer novas espécies. Aspectos ecológicos e zoo- e paleozoogeográficos também foram brevemente discutidos.

The present study is a further contribution to the systematic knowledge of the shallow water marine ostracodes from the Brazilian oceanic islands. A total of 14 species belonging to 10 genera and eight families is herein identified. One new genus and species are described and illustrated: Berguecythere insularis gen. nov., sp. nov. In addition to this new taxon, the abundant species Loxocorniculum tricornatum Krutak, 1971, widely distributed in recent sediments in the Gulf of Mexico, Caribbean, north and northeast of Brazil and the Rocas Atoll, along with the cosmopolitan tropical ostracode Triebelina sertata Triebel, 1948, were also identified at specific level. The remaining 11 species were left at the genus level, and should provide new species. Ecological, zoo- and paleozoogeographical aspects were also briefly discussed.

As assembléias de ostracodes do sistema estuarino-lagunar de Cananéia-Iguape são pela primeira vez aqui discutidas em detalhe. Foram coletadas amostras em trinta e quatro pontos, eqüidistantes aproximadamente 1 km, incluindo o mar de Cananéia, mar Pequeno, mar de Cubatão, rio Ribeira de Iguape e rio Itapitangui. A ostracofauna mostrou-se pouco abundante e diversificada, contabilizando um total de apenas 662 espécimens entre vivos e mortos. As espécies mais abundantes são eurihalinas: Cyprideis multidentata Hartmann, 1955 (174 espécimens), Minicythere heinii Ornellas, 1974 (54 espécimens), Tanella gracilis Kingma, 1948 (96 espécimens) e Whatleyella sanguinettiae Coimbra, Carreño & Ferron, 1994 (226 espécimens). Embora existam poucos estudos sobre ostracodes mixohalinos no Brasil - inclusive dos táxons marinhos marginais tipicamente eurihalinos - uma revisão bibliográfica exaustiva mostrou que eles são melhor conhecidos nas regiões sul e sudeste. Com base nesta revisão e nos novos dados aqui apresentados, discute-se a distribuição geográfica das oito espécies mais características das áreas mixohalinas do sul e sudeste do país.

The ostracode assemblages from Cananéia-Iguape estuarine/lagoon system (southernmost State of São Paulo) are here discussed in detail for the first time. Thirty-four sites, approximately 1 km equidistant, were sampled along the system, including the Cananéia Sea, Pequeno Sea, Cubatão Sea, Ribeira de Iguape River and Itapitangui River. The ostracodes throughout this area have poor assemblages, with a total of 662 specimens of dead and living organisms. The majority of the ostracode fauna is composed of euryhaline species, as follows: Cyprideis multidentata Hartmann, 1955 (174 specimens), Minicythere heinii Ornellas, 1974 (54 specimens), Tanella gracilis Kingma, 1948 (96 specimens) and Whatleyella sanguinettiae Coimbra, Carreño & Ferron, 1994 (226 specimens). Although there are few studies on the Brazilian mixohaline ostracode faunas, including the euryhaline marginal marine taxa, the published data show that the group is best known in the south and southeast regions. Based on this review and with the new data presented in this paper, the geographical distribution of eight mixohaline key species in southern and southeastern Brazil is also discussed.