Eastern Brazilian Coast Research Articles

Geomorphological evolution in transitional environments on the eastern coast of Brazil

Geomorphological evolution in transitional environments on the eastern coast of Brazil

The good, the bad and the boa: An unexpected new species of a true boa revealed by morphological and molecular evidence.

Snakes of the genus Boa are outstanding elements of the New World biota with a broad sociological influence on pop culture. Historically, several taxa have been recognized in the past 300 years, being mostly described in the early days of binomial nomenclature. As a rule, these taxa were recognized based on a suite of phenotypic characters mainly those from the external morphology. However, there is a huge disagreement with respect to the current taxonomy and available molecular phylogenies. In order to reconcile both lines of evidence, we investigate the phylogenetic reconstruction (using mitochondrial and nuclear genes) of the genus in parallel to the detailed study of some phenotypic systems from a geographically representative sample of the cis-Andean mainland Boa constrictor. We used cyt-b only (744bp) from 73 samples, and cyt-b, ND4, NTF3, and ODC partial sequences (in a total of 2305 bp) from 35 samples, comprising nine currently recognized taxa (species or subspecies), to infer phylogenetic relationships of boas. Topologies recovered along all the analyses and genetic distances obtained allied to a unique combination of morphological traits (colouration, pholidosis, meristic, morphometric, and male genitalia features) allowed us to recognize B. constrictor lato sensu, B. nebulosa, B. occidentalis, B. orophias and a distinct lineage from the eastern coast of Brazil, which we describe here as a new species, diagnosing it from the previously recognized taxa. Finally, we discuss the minimally necessary changes in the taxonomy of Boa constrictor complex; the value of some usually disregarded phenotypic character system; and we highlight the urgency of continuing environmental policy to preserve one of the most impacted Brazilian hotspots, the Atlantic Forest, which represents an ecoregion full of endemism.

Depositional and diagenetic characteristics of the Lula's Fingers: Evidences of microbial activity and exposure during final pre-salt depositional in Santos Basin

Over the past decade, considerable progress has been made in the understanding of non-marine carbonate rocks following the discovery of substantial oil reserves in the pre-salt region off the eastern coast of Brazil. The Lula's Fingers interval, situated at the top of the Barra Velha Formation, has been identified in gamma-ray log patterns as a crucial stratigraphic marker for the pre-salt deposits in the Santos Basin. Despite its stratigraphic significance, comprehensive sedimentological and petrographic studies on this interval are lacking. This absence of detail studies may be associated with the recurrence of fine-grained non-marine carbonate rocks. This study employs a range of techniques, including classical sedimentology (macro- and microscopic description), Markov Chain analysis, and complementary methods such as quantitative analysis using XRD, SEM-EDS, cathodoluminescence, and epifluorescence. These techniques are used to evaluate the sedimentological and diagenetic characteristics of the fine-grained non-marine carbonate rocks in Lula's Fingers interval. In general terms, the interval consists of in situ rocks formed through abiotic chemical precipitation (such as parallel-laminated calcilutite, laminated spherulestone, and shrubstone), as well as reworked calcarenites and calcirudites formed under high-energy conditions, resembling those described for the Barra Velha Formation. However, it differs primarily from the main Barra Velha deposits in the presence of (i) calcilutite exhibiting crenulated lamination, peloidal/pseudo-peloidal to clotted texture, and microbial lumps, providing substantial evidence of microbial activity, and (ii) nodular calcilutites with a pseudo-particulate texture. The presence of nodular calcilutites suggests that the deposition of the Lula's Fingers interval occurred in shallow to very shallow settings, occasionally experiencing subaerial exposure, in contrast to the alkaline lake settings interpreted for most of the Barra Velha Formation. Dolomitization and silicification within the Lula's Fingers interval have significantly altered the rocks, hindering the identification of primary texture and composition. Silica and dolomite commonly fill pores and function as replacive minerals across various lithofacies and microfacies. Lamellar dolomite emerges as the dominant texture within the study succession, often filling interstices between spherules and shrubs. Its presence is likely associated with a precursor detrital or authigenic material, possibly a magnesium clay matrix, which still influences the final texture of the rock despite complete replacement.

The effect of a mining dam failure on the genetic diversity and population resilience of marine fishes along the eastern Brazilian coast

We used microsatellite DNA markers to examine the impact of the Fundão Dam failure, one of the world’s worst mining-related environmental disasters, on the genetic diversity of four marine and estuarine fishes across the Brazilian east coast's continental shelf and estuarine ecosystems. The strong mud flow along the Doce River and nearby areas resulted in changes in genetic diversity, with all species exhibiting low genetic diversity indices, primarily in estuarine species, and particularly those with a greater association with the substrate. Furthermore, the low M-ratio values in all species tested indicated a recent decrease in the effective population size. Estuarine species, particularly the slipper sole Trinectes paulistanus, were more directly impacted by the mud plume than marine species. The loss of genetic variability due to population decline is concerning because it is ultimately an important component in determining the ability of marine fishes to adapt to environmental changes. Combining genetic data from four fish species with different behaviours, habitats, life histories, and economic values revealed that genetic diversity was a valuable tool for assessing the effects of the Fundão Dam failure.

Distribution and habitat use modelling from satellite tracking data of humpback whales in Brazil agrees with shipboard survey data modelling

Statistical modelling of animal distributions has been widely applied to explain how mobile species use their habitats. The distribution of and habitat use by humpback whalesMegaptera novaeangliaeoff the eastern coast of Brazil have previously been investigated by modelling visual survey data. Here, we modelled distribution in their breeding range using individual tracking data to compare ecological inferences with those from previous models from line transect data. A generalised estimating equation framework was used to model the tracking data and pseudo-absences as functions of spatial covariates. Covariates considered were latitude and longitude, sea surface temperature (SST), current and wind speeds near the surface, distances to shelf-break and the coast, sea bottom depth and slope, and a factor variable representing ‘shelter’. Two modelling exercises were developed: a habitat use model (HUM) and a distribution model (DIM). Covariates retained in the selected HUM were SST, distance to coast and shelf-break, current and wind speeds and shelter. Covariates retained in the selected DIM were latitude/longitude, current speed and distances to shelf-break and coast. The modelled relationships between whale occurrence and environmental covariates using tracking data were similar to those using line transect data. Distribution maps were also similar, supporting higher densities around the Abrolhos Archipelago and to its south. We showed that habitat use and distribution of this population in the area could be similarly inferred by modelling either line transect or tracking data. Using these 2 approaches in conjunction can strengthen the understanding of important ecological aspects of animal populations.

Estimation of the Size and Type of Porosity in an Albian Carbonate Reservoir of the Campos Basin, Southeastern Brazil

Abstract —The Albian carbonates of the Quissama Formation in the Campos Basin, southeastern Brazil, are important oil reservoirs. They make part of a carbonate platform that formed along the eastern coast of Brazil and the western coast of Africa during the Albian, which resulted in the opening of the South Atlantic Ocean. Subsequently, this reservoir was subjected to different postdepositional diagenetic processes. The present study utilized geophysical well logs to estimate the porosity of this reservoir, based on density, neutron porosity, and sonic logs. The estimates do not show good results when compared with the laboratory measurements. Then, exploring the fact that these logs are obtained with different physical principles, a multiple linear regression and an artificial neural network with Bayesian stochastic approach were applied, which resulted in a better porosity estimate. As porosity is a petrophysical parameter considered significant in the characterization of reservoirs, it was used, hereafter, to estimate permeability and water saturation of the reservoir, applying empirical equations. From there, it was not enough just to estimate the porosity, but was necessary to know what type it is. For this purpose, the concepts of the electrical formation factor, cementation coefficient, tortuosity, and anisotropy were used. With them, the zones with primary intergranular and interparticle porosity as well as secondary porosity, such as fractures, fissures, and vugs, were mapped. It was concluded that, with studies of this type, it is also possible to identify the connected and nonconnected porosities, which permits estimation of the effective porosity along the well.

Fish biodiversity of a tropical estuary under severe anthropic pressure (Doce River, Brazil)

Abstract The Doce River has undergone severe changes over the last centuries (e.g., flow regulation, pollution, habitat and species loss). Here, we present the first comprehensive fish biodiversity assessment of the Doce River estuary and a summary of the main impacts and their drivers for the whole river since the early 18th century. Carangiformes, Siluriformes and Eupercaria incertae sedis were the most representative orders for the 115 species recorded. Most species are native (87.8%), euryhaline/peripheral (80%) and zoobenthivorous (33.9%). Threatened (Paragenidens grandoculis, Genidens barbus, and Lutjanus cyanopterus) and near threatened (Cynoscion acoupa, Dormitator maculatus, Lutjanus jocu, Lutjanus synagris, and Mugil liza) species are peripheral. Thirteen species are exotic at the country (Butis koilomatodon, Coptodon rendalli, and Oreochromis niloticus) or the basin level (e.g., Pygocentrus nattereri and Salminus brasiliensis). The catfish Cathorops cf. arenatus is reported for the first time on the eastern coast of Brazil and Paragenidens grandoculis, considered extinct in the Doce River, was discovered in the estuary.

Pet distribution modelling: Untangling the invasive potential of Trachemys dorbigni (Emydidae) in the Americas.

Human activities have been changing the global biogeographic patterns by the introductions of invasive species. For reptiles, the invasion rate increase of non-native species is remarkably related to the pet trade, especially for freshwater turtles. Here we estimated the invasive potential of the South American turtle Trachemys dorbigni in the Americas using a combination of climatic and human activity variables. We built species distribution models based on data from the native and invasive ranges, using the ensemble model from five different algorithms (GAM, MAXENT, BRT, RF and GBM). We compared the two models’ performance and predictions, one calibrated with only climatic variables (climate-driven), and the second also included a descriptive variable of human activity (climate plus human-driven). Suitable areas for T. dorbigni covered occurrence areas of its congeners and highly diversified ecoregions, such as the eastern USA, the islands of Central America, and the south eastern and eastern Brazilian coast. Our results indicate that human activities allow T. dorbigni to establish populations outside of its original climatic niche. Including human activity variables proved fundamental to refining the results to identify more susceptible areas to invasion and to allow the efficient targeting of prevention measures. Finally, we suggested a set of actions to prevent T. dorbigni becoming a highly impacting species in the areas identified as more prone to its invasion.

Invasive plants in Brazil: climate change effects and detection of suitable areas within conservation units

Invasive exotic plants may compromise the survival, growth, and reproduction of native species and are among the leading causes of worldwide biodiversity losses. Climate changes—which will affect species distribution—may even amplify the problems caused by invasive species. Here, we used ecological niche models to evaluate the current and future distribution of 108 invasive plants in the entire Brazilian territory and the country's conservation unit facilities (CUFs). Overall, our results did not indicate a significant change in the potential distribution of invasive plants between the current and future climate scenarios, although we expect that 67.5% of the species will decrease its range in Brazil in the future. The proportion of the plants' invasive range inside conservation units varied from 1 to 12%, and results suggest that this would not increase or decrease in the future. Taken together, our results do not indicate that climate change will amplify the effects of existing invasive plants—although it may facilitate the invasion of other species. Both current and future scenarios suggest high suitability for invasive plants in the southern, southern, southeastern, and eastern coast of Brazil, comprising the Caatinga, Cerrado, and Mata Atlântica Brazilian biomes, the most populated areas of the country. We advise that conservation unit managers and authorities within these regions should continuously monitor such invasive plants to take early responses to avoid their establishment.

Estimates of population growth rates of humpback whales (Megaptera novaeangliae) in the wintering grounds off the coast of Brazil (Breeding Stock A)

Humpback whales wintering off the eastern coast of Brazil were heavily exploited by commercial whaling in the Southern Hemisphere. During recent years, clear signs of recovery have been observed, but few estimates of population growth rate exist. In this study, quantitative estimates of rates of population increase are obtained from sighting per unit of effort data (1995–98) using generalised linear models and maximum likelihood estimation. The error distributions considered for the models were Poisson and negative binomial. Predictors of the number of sightings included the year, month and 2-week periods during which the sightings were made. Predictors were treated as factors or numeric variables. For the numeric variables, quadratic dependence was also considered for each predictor to allow for possible non-linear relationships. Using Akaike Information Criterion (AICc) as a model selection criterion, the best model included year and month as continuous predictors. The data indicated strong support for the negative binomial over the Poisson models, but did not support models based on a finer temporal scale than month. Assuming year to be a linear predictor, the best estimate of the growth rate for the population wintering off Brazil was 7.4% per year (95% CI = 0.6–14.5%) during the period 1995–98. This estimate provides additional quantitative evidence that this population has been increasing and is consistent with the observed growth rates of other humpback whale stocks.

Geographic restriction, genetic divergence, and morphological disparity in the Brazilian Atlantic Forests: Insights from Leposoma lizards (Gymnophthalmidae, Squamata)

Lineage differentiation, long-term persistence, and range limitation promote high levels of phylogenetic and phylogeographic endemisms and likely underlie the abundant morphologically cryptic diversity observed in the Brazilian Atlantic Forests (AF). We explore lineage differentiation and range restriction in the AF and ask if genetic divergence and morphological disparity are correlated by integrating coalescent-based species delimitation, molecular phylogenetic, and morphological analyses in the lizard genus Leposoma. We present the first species tree for Leposoma and of their tribe, the Ecpleopodini. The analyses are based on the largest dataset ever assembled for Leposoma in terms of number of species (all represented), genetic markers (12 loci), and geographic coverage (~2,500 km). The exercise allows us to robustly delimit species within the genus and phylogeographic lineages within all species. We find support for the monophyly of the genus and for the recognition of a yet undescribed species around the Baía de Todos-os-Santos, in the state of Bahia; this form is distinct from all other congeners, both genetically and morphologically. We find that L. baturitensis, from the northeastern state of Ceará, is basal to the genus – and sister to a clade of six species restricted to the AF across the eastern coast of Brazil. Relationships within this coastal clade are ((((L. annectans, Leposoma sp.), L. scincoides), L. puk) (L. nanodactylus, L. sinepollex)). Phylogenetic and phylogeographic analyses, together with precise distribution data, allowed us to update the ranges of species and phylogeographic lineages. We reveal pervasive geographic restriction of divergent lineages in Leposoma at and below species level and discuss how forest refuges and rivers might have contributed to it. We find that morphological disparity lags behind genetic divergence in the genus because although they are correlated, the first accumulates at a much slower rate than the latter. We hope to encourage new studies in the area of AF north of the Doce river; phylogeographic sampling in that region has been much less common relative to southern sites, yet it may hold the key to several important processes defining biodiversity patterns in eastern Brazil. This appears to specially apply to processes underlying geographic restriction of morphologically cryptic, yet genetic divergent lineages, as the case of Leposoma.

Depositional and diagenetic processes in the pre-salt rift section of a Santos Basin area, SE Brazil

ABSTRACT This study aims to provide a better understanding of the genesis and diagenetic evolution of the rift pre-salt deposits of the Santos Basin, in the context of evolution of the lake system in which the sediments were deposited. The study of the syngenetic and early diagenetic constituents and their paragenetic relations allowed reconstruction of the evolution of lacustrine environmental conditions during the rift stage in the central area of the basin. A petrological study was performed on cores and sidewall samples of a well drilled through the pre-salt rift section in the Lower Cretaceous of the central Santos Basin, eastern Brazilian coast. The studied rocks consist of carbonate and non-carbonate intrabasinal components, with extrabasinal non-carbonate contribution. During Barremian early rift sedimentation, intense syngenetic precipitation of magnesian clay minerals under highly alkaline conditions deposited arenites constituted by stevensite ooids and peloids, as well as hybrid, resedimented deposits of the Piçarras Formation. Freshening of the lacustrine environment provided the conditions required for the proliferation of bivalves and sedimentation of the coquinas of the Itapema Formation. The massive structure of the deposits, poor sorting, chaotic to concave-up orientation of the bioclasts, and mixing of bivalves with stevensite particles indicate redeposition by gravity flows. The main diagenetic processes in rift stevensite and hybrid rocks are the cementation and replacement of grains by calcite, dolomite, and subordinately, silica and smectite. Siliciclastic-volcaniclastic mudrocks present intense replacement by dolomite. In the bivalve rudstones, the main diagenetic processes were dissolution of the shells and cementation of the intraparticle and interparticle pores by calcite and, subordinately, dolomite and silica.

Heterogeneity of rhodolith beds expressed in backscatter data

Rhodoliths play a major role as benthic habitats and are important calcium carbonate bio-factories. Several studies have acoustically mapped rhodolith beds as a homogeneous habitat but spatial changes in nodule coverage, or density, commonly occur. Here, the objective is to acoustically recognize heterogeneities in rhodolith bed structure using the response of backscatter to map changes in nodule coverage and density. High-resolution multibeam sonar (MBSS) data were acquired on April 2018, in the Marine Protection Area (MPA) Costas das Algas, located in the Espírito Santo continental shelf, Eastern Brazilian coast. Three areas were selected based on available data, totalizing 73km2 of data acquisition. Ground truth was obtained at 80 stations, using a drop camera system. Seabed classification was determined by applying an image segmentation process on multibeam sonar backscatter mosaic. Ground truth data was used to statistically show the relation between backscatter and seabed types. Results identified three classes related to rhodoliths in different coverage densities: low rhodolith coverage (inferior to 25% of rhodoliths over a determined area), moderate rhodolith coverage (between 25% and 35% of rhodoliths), and high rhodolith coverage (>35%). Classes associated with sediment, bioconcretions and red algae genus Peyssonelias were also identified. A map showing changes in rhodolith coverage across the shelf depth gradient were produced. The seabed classes had a statistically significant correlation with the segmented backscatter classes. In general, higher rhodolith coverage correlates with higher backscatter. The backscatter mosaic over the area is marked by an extensive presence of the red algae Peyssonelias, resulting in a lower correlation index, when compared to the areas with no Peyssonelia. The seabed mapping approach used in this work provided an efficacious tool to map benthic habitats and to detail nodules distribution across a rhodolith bed. Moreover, the recognition of heterogeneities in rhodolith bed structure provides important information for monitoring and protecting these vulnerable marine ecosystems. The main driver of the coralligenous algae nodule coverage, in the research area, seems to be the morphology of the area and the influence of mesoscale circulation.

Diet and foraging opportunism of the Guiana dolphin (Sotalia guianensis) in the Abrolhos Bank, Brazil

AbstractDiet analysis allows exploring how coastal dolphins interact with the environment and their role in the marine food webs. We studied the diet and feeding ecology of the Guiana dolphin, Sotalia guianensis, through analysis of stomach content from 42 animals stranded on the eastern coast of Brazil. A total of 1,336 semidigested prey items (fish, otoliths, cephalopod beaks, and crustaceans) were identified. Teleost fish comprised the most frequent food item (92% of the total), followed by cephalopods, and crustaceans. Prey belonged to 34 taxa and richness in individual stomachs varied from 1 to 15 prey taxa. Prey were generally small, but showed a significant trend to increase in size with dolphin length. The main prey of Guiana dolphins were demersal, estuarine, and sound‐making fish such as catfish and sciaenids. No sex‐related differences in diet were found. Diet composition varied seasonally and occurrence of prey items was coherent with breeding or high abundance periods of some fish species and squids. Our study shows the importance of demersal prey from estuarine and soft‐sediment habitats to Guiana dolphin in the Abrolhos Bank and reveals that feeding habits are generalist and opportunistic, with diet reflecting the seasonal abundance and availability of prey.

The Santo Antônio Bank: a high-resolution seismic study of a deflected ebb-tidal delta located at the entrance of a large tropical bay, eastern Brazil

The Santo Antonio Bank (SAB) is a large sand accumulation on the inner continental shelf of Salvador City, next to Todos os Santos Bay (TSB) entrance, eastern Brazilian coast. Since the sixteenth century, chroniclers report this feature as a navigational hazard. Previous studies have tried to determine the origin and volume of sands stored within this feature without success. In the present study, high-resolution shallow seismic surveys were used to investigate the architecture, origin, and evolution of the SAB. One hundred seventy kilometers of high resolution shallow seismic lines was acquired during December 2014 and February 2015 using a Meridata® sparker system operating on frequencies between 0.3 and 1.5 kHz, with a maximum 200 J of energy. Three major stratigraphic units were identified: the bedrock, a transgressive unit, and a highstand unit. The bedrock comprises sedimentary rocks of the Northern Camamu Sedimentary Basin and high-grade metamorphic rocks of the Precambrian basement. The transgressive unit is interpreted as the result of deposition in an estuarine environment infilling incised valleys. The highstand unit represents the SAB itself. A well-preserved proto-bank exists at the core of the SAB marking the early stages of bank development. This proto-bank drowned in place possibly during the 8.2-ka event. Present-day SAB and tidal prism volumes show that the bank reached a maturity phase of development. The volume of siliciclastic sands stored in the SAB is 5.98 × 108 m3. The SAB is potentially a major source of sands for beach nourishment for the urban beaches of the city of Salvador and metropolitan area, thus increasing the resilience of the city to future sea-level rises.

Sharing the space: Review of humpback whale occurrence in the Amazonian Equatorial Coast

Humpback whales have a cosmopolitan distribution and undertake annual migrations between low and high latitudes where breeding and feeding takes place, respectively. In Brazil, the main breeding area encompasses the Abrolhos Bank at the Eastern Brazilian Coast and the feeding area of this population is located in South Georgia and South Sandwich Islands. Here, two recent records of humpback whales are reported for Maranhão State, Amazonian Equatorial Coast (AEC), one of which involves a newborn calf with remains of the umbilical cord. Additionally, an in-depth review of the stranding and observation records for this area is presented. Phylogenetic analysis placed the stranded animals within the two most common haplogroups reported for the Southern Hemisphere breeding grounds (CD and IJ). A possible extension of the species range or the recolonization of a historical breeding area along the Brazilian coast is discussed. Presented results provide evidence of distribution overlap between the humpback whale populations of the northern and southern Atlantic Ocean which will require the development of conservation strategies among neighboring countries and underline the need to develop management strategies that will allow sustainable management of the Amazonian Equatorial Coast.

New records of the snow bass Serranus chionaraia (Perciformes: Serranidae) confirm an established population in the Brazilian Province.

The snow bass Serranus chionaraia is a small-bodied reef fish presumed to be restricted to the Caribbean Province, with a single specimen captured south of the Amazon River mouth. Recent surveys with baited remote underwater stereo-video systems detected the species c. 1900 km southward. Meristic and morphometric characters of two specimens examined in this study confirmed the species identity, which greatly extends the species' range southward on the eastern coast of Brazil and indicates the presence of an established population of S. chionaraia in the Brazilian Province.

Genetic Population Structure of White Grunt in the Southeastern United States

AbstractThe White Grunt Haemulon plumierii is a reef‐associated coastal fish species in the western Atlantic Ocean that occurs from the Chesapeake Bay south through the Gulf of Mexico and along the eastern coast of Brazil. In U.S. waters, there are recreational and commercial fisheries for White Grunt, but there are currently no size regulations in the recreational fishery and no size or trip regulations in the commercial fishery. A stock assessment for White Grunt is necessary prior to enacting any potential future regulations, and informed stock boundaries must first be delineated. Studies finding regional differences in genetic population structure and growth rates for White Grunt in the southeastern USA have resulted in uncertainty of stock definition. The objective of the present study was to evaluate the genetic population structure of White Grunt in the southeastern USA and the U.S. Virgin Islands using 10 microsatellite markers. Pairwise genetic distances, allele frequency distributions, principal coordinates analysis, and Bayesian clustering results indicated that White Grunt should be separated into four distinct populations among the regions sampled: the Carolinas (North Carolina and South Carolina); southeast Florida, including the Florida Keys (from Cape Canaveral to Key West); eastern Gulf of Mexico (western coast of Florida north of Key West); and the U.S. Caribbean. The genetic differentiation results presented here, along with regional growth studies, warrant the management of White Grunt as three separate stocks in the Atlantic Ocean bordering the continental USA: the Carolinas, southeast Florida and Florida Keys, and the eastern Gulf of Mexico, with at least one other separate stock in the Caribbean Sea.

Lower diversity of recruits in coastal reef assemblages are associated with higher sea temperatures in the tropical South Atlantic

Climate change will lead to community shifts and increase the vulnerability of coastal marine ecosystems, but there is yet insufficient detail of how early life stages of marine populations are linked to oceanic-climate dynamics. This study aimed to investigate how ocean-climate variability is associated with spatial and temporal changes in benthic larval recruitment of tropical reef assemblages. Recruitment (abundance, richness, and diversity) of benthic invertebrates was monitored for one year on macroalgal beds in four rocky reefs in a marine protected region in the Eastern coast of Brazil, and compared to fluctuations in meteo-oceanographic conditions at multiple temporal scales (days, weeks, and months). Our results revealed that recruitment of benthic invertebrates varies widely (up to 15 orders of magnitude) among sampled reefs and in time, with wave height, wind speed, and sea temperature being significantly related to recruitment variability. We detected strong taxonomic variability in recruitment success and ocean-climate variables, which highlights the complexity of estimating community vulnerability to climate change in benthic communities. Given that macroalgal beds are key to recruitment of some species regionally (4–30 km), the protection of coastal nursery habitats may be critical for marine conservation and species adaptation in a climate change scenario. Considering the projected ocean-climate change in IPCC scenarios, our study suggests that recruitment of marine populations in coastal reefs could be highly sensitive to climate change in the tropical South Atlantic Ocean.

Redescription of Orthopristis ruber and Orthopristis scapularis (Haemulidae: Perciformes), with a hybridization zone off the Atlantic coast of South America.

The genus Orthopristis includes seven valid species, three from the western Atlantic and five from eastern Pacific, while the available identification guides and taxonomic keys incorrectly recognize Orthopristis ruber as the only valid species found on the Atlantic coast of South America. Efforts to expand the inventory of fish species from the northern coast of Brazil led to the identification of two distinct species of Orthopristis from Atlantic South America, based on the analysis of coloration patterns and meristic data, as well as DNA. In the present study, the limits of Orthopristis ruber are reviewed, while Orthopristis scapularis is recognized as a valid species for the northern and northeastern coasts of South America. Based on intermediate morphological characteristics and nuclear DNA markers, a hybrid zone was identified off the state of Espírito Santo, on the eastern Brazilian coast. Additionally, considerations are made on the diversity and biogeography of the coastal marine and estuarine fishes found on the Brazilian coast.