Geochemical, mineralogical, and palynological records from a Holocene sediment core 12.7 m long from Lake Silvana, southeastern Brazil, served to identify the source of detrital sediments within catchment soils. The lake basin was first flooded in the early Holocene (9400 14C yr B.P.), when a gibbsite-rich B soil horizon started to accumulate. Four distinct hydrologic phases are consistent with vegetational changes indicated by pollen data. Phases of slope instability (colluviation) and low lake level correspond to pollen-free intervals and point to a severe retreat of the vegetation cover. The rapid sedimentation of slope-wash sediments alternating with alluvial sediments appears to have formed a tributary fan 7.8 m thick that dammed the Lake Silvana Basin 8500 14C yr B.P., probably as a response to a drastic increase in precipitation rates.

The lack of paleoecological records from the montane Atlantic Rainforest of coastal Brazil, a hotspot of biological diversity, has been a major obstacle to our understanding of the vegetational changes since the last glacial cycle. We present carbon isotope and pollen records to assess the impact of the glaciation on the native vegetation of the Serra do Mar rainforest in São Paulo, Brazil. From ca. 28,000 to ∼ 22,000 14C yr BP, a subtropical forest with conifer trees is indicative of cool and humid conditions. In agreement carbon isotopic data on soil organic matter suggest the presence of C3 plants and perhaps C4 plants from ∼ 28,000 to ∼ 19,000 14C yr BP. The significant increase in the sedimentation rate and algal spores from ∼ 19,450 to ∼ 19,000 14C yr BP indicates increasing humidity, associated to an erosion process between ∼ 19,000 and ∼ 15,600 14C yr BP. From ∼ 15,600 14C yr BP to present there is a substantial increase in arboreal elements and herbs, indicating more humid and warmer climate. From ∼ 19,000 to ∼ 1000 14C yr BP, δ13C values indicated the predominance of C3 plants. These results are in agreement with studies in speleothems of caves, which suggest humid conditions during the last glacial maximum.

Artificial reefs (ARs) are often used to improve fishing and, consequently, the economy of a region. However, the way in which the species use the reefs may vary between fish assemblages. An assessment was made of the influence of an AR complex on the transient fish population off the northern coast of Rio de Janeiro state and, therefore, two control areas were sampled. Gillnets were used to capture individual fish in six sampling surveys. Cumulative abundance and biomass curves (ABC) were used to assess the possible effects of the reefs on the community's functional structure. In the dry season, during which the influence of the Paraíba do Sul River is smaller, a larger richness of r-strategy species and juveniles of K-strategy species was observed in the reef area compared with the control areas, suggesting that the AR acts as a protective environment for these species. During the lower river discharge period the results indicated a potential disturbance in the functional structure of the AR fish community and, therefore, a less stable environment relative to the control areas. This ‘instability’ warrants a positive connotation, as it indicates that the artificial reefs are harbouring species that are particularly sensitive to predation, making the reef a powerful tool for maintaining these populations on the northern coast of Rio de Janeiro.

Microvelia picinguaba sp. nov., Microvelia ubatuba sp. nov., Paravelia gabrielae sp. nov. and Rhagovelia pseudotijuca sp. nov. are described. The male of Microvelia ioana is described. Microvelia mimula and Microvelia aemulana are synonymized. Microvelia hinei, M. ioana, Microvelia longipes, Microvelia pulchella, Microvelia venustatis, Oiovelia brasiliensis, Oiovelia cunucunumana, Paravelia basalis, Paravelia itatiayana, Rhagovelia denticulata, Rhagovelia hambletoni, Rhagovelia janeira, Rhagovelia robusta, Rhagovelia tenuipes, Rhagovelia zela and Stridulivelia ayacucho are recorded for the first time from São Paulo State. New locality records are given for Husseyella diffidens, Rhagovelia accedens, Rhagovelia aiuruoca, Rhagovelia henryi, Rhagovelia lucida, Rhagovelia modesta, Rhagovelia occulcata, Rhagovelia trepida and Rhagovelia triangula.