may represent areas of reproduction, protection and feeding for some marine species, including commercially important. The east coast of Rio Grande do Norte is composed by small and medium-sized basins partially or fully inserted in the Atlantic Forest, representing the northern extreme of this biome, with only 4.1% of the native vegetation (Fundação SOS Mata Atlântica and INPE 2012), composed by small isolated fragments. Therefore, the aim of this study was to inventory the ichthyofauna of the coastal Pratagi River basin, located on the east coast of the state, region with intense tourist activities, and report the main anthropogenic impacts on the basin, to increase the knowledge and support to conservation strategies for the Atlantic Forest fish fauna. Material and Methods Study site The study was conducted in Pratagi River basin, located in Ceará-Mirim Municipality, Rio Grande do Norte State. The main course of the Pratagi River has about 10 km long and is a tourist natural attraction of Rio Grande do Norte coast due to its high landscape value, with two popular sites mainly visited by tourists who make buggy rides in dune areas at the east coast, the Lavacu and Cachoeirinha Pitangui waterfall. The Pratagi River mouth is distant about 30 km from Natal, state capital city, and the main river course presents excerpts with clear waters fringed by dunes in Restinga and Atlantic Forest remnants until emptying into the Atlantic Ocean (Figure 1). Data collection Eleven samples were taken from five sites along Pratagi River basin, from the headwaters to the estuarine portion.

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This study examined population density, habitat and diet of Dasyatis marianae, a recently discovered species, in the reef complex of Maracajaú in Rio Grande do Norte state, Brazil. The highest concentration of D. marianae occurred in seagrass beds. Habitat use differed significantly between sex and age classes, with females and juveniles using areas other than reefs. Females utilized primarily seagrass beds and juveniles occurred mainly along the sandy bottom near the beach, highlighting the importance of protecting these areas. Dasyatis marianae diet was characterized primarily by crustaceans (91·9% index of relative importance, I ), including shrimp, crabs and lobsters. The availability of prey in different habitat types influences occupation by D. marianae, but the prey selectivity of D. marianae, among other factors, may affect this relationship. Intense shrimp and lobster fishing in the region probably has an effect on preferred prey resources of this ray. Information on feeding habits of this species contributes to a better understanding of trophic dynamics and food webs, which is critical if ecosystem principles are to be integrated into fisheries management.

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Revista Brasileira de Zoologia 23 (3): 817-823, setembro, 2006Peixes litorâneos residentes são aqueles que passam toda a vida na região entre-marés, dentre os quais estão incluídos os representantes das famílias Gobiidae, Blenniidae, Labrisomidae e Tripterygiidae (DEMARTINI 1999). Amborés e peixes-macaco, como são popularmente conhecidos os gobiídeos e bleniídeos respectivamente, em Fernando de Noronha também são chamados de maria-da-toca (representantes das famílias Labrisomidae e Blenniidae), limpa-limo e peixe-cobra (Blenniidae). São comuns em águas rasas (zona litorânea), escondem-se em tocas recifais, corais, esponjas, sob algas e abrigos rochosos, compondo parte da chamada ictiofauna invisível, que interage com outros organismos residentes. A presença de abrigos adequados é (Gobiidae and Bleniidae) are the most important group of small benthic littoral fishes in tropical reefs, representing most of the high number of small fish species found in Western Atlantic. The natural history of gobiid and bleniid fish from Fernando de Noronha was assessed by means observation sessions using both snorkelling and scuba diving. Most of these observations were aimed at social behaviour, such as intra and interespecific interactions, territorial and reproductive behaviour. In general, these fish from Fernando de Noronha occurs in intertidal zone, are gregarious, with small home ranges of near 2 x 2 m 2 , and show low agressivity towards other fish. Occasionally, some chasing was recorded between individuals of the same or distinct species. Low agressivity is probably associated to the occupation of small areas (e.g. tide pools), as a high degree of agressivity may represent an unnecessary [excessive] waste of energy. Most of the studied species presents cryptic coloration, associated to the avoidance of predators, but some males showed conspicuous coloration and intense aggressive behaviour, mainly during the reproductive season. It was only during this occasion that territorial behaviour, chasing and bites were recorded. KEY WORDS. Preferencial habitat; reproductive aspects; social behaviour.RESUMO. Os amborês e peixes-macaco, como são popularmente conhecidos gobiídeos e bleniídeos, são elementos dominantes da fauna de pequenos peixes bentônicos e litorâneos que habitam recifes tropicais, compondo grande parte da alta diversidade das espécies de pequeno porte encontrada no Atlântico ocidental. O estudo da distribuição e história natural dos gobióides e blenióides de Fernando de Noronha foi desenvolvido através de observações de campo. Além da descrição dos hábitats preferenciais foram abordados aspectos sociais tais como, habitat preferencial, interações intra-e interespecíficas, comportamento domiciliar e territorial, e comportamento reprodutivo. A maioria das espécies em foco apresenta distribuição principalmente litorânea, são gregárias, com áreas domiciliares relativamente pequenas em torno de 2 x 2 m 2 , pouco agressivas, tendo sido ocasionalmente registradas curtas perseguições intra-e interespecíficas. A baixa ...

The Tropical Southwestern Atlantic is characterized by prominent ecosystems with large-scale oceanographic complexity. Yet, the evolutionary processes underlying genetic differentiation and connectivity in this region remain largely unknown. Entomacrodus vomerinus (Valenciennes, 1836) is a demersal fish with planktonic larvae endemic to this marine province, inhabiting shallow tidal pools in continental and oceanic reef environments. We evaluated the population structure, genetic diversity and gene flow of E. vomerinus using mitochondrial data (CYTB and COI) and nuclear (rhodopsin, RHO) DNA sequences. We sampled a total of 85 individuals, comprising 46 from three oceanic archipelagos with varying distance from the coast (São Pedro and São Paulo—SS, Fernando de Noronha—FE and Rocas Atoll—RA) and 39 from two localities in northeastern Brazilian coast (Rio Grande do Norte—RN and Bahia—BA). Multilocus analysis revealed the presence of three Evolutionarily Significant Units—ESUs (SS, FE+RA, and RN+BA), which are in accordance with distinct marine ecoregions. Coalescent analyses showed that the central ESU has a larger effective population size than the other two, suggesting strong asymmetries in the genetic diversity across the species range. Moreover, they showed that gene flow is highly asymmetric, suggesting a source-sink dynamics from the central ESU into the remaining ones, in agreement with oceanic currents. Together, these results provide insights in the evolutionary mechanisms facilitating diversification in this marine province.

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Species of the family Blenniidae from Fernando de Noronha Archipelago (03°51’S, 32°26’W), an oceanic island 345 km off northeastern Brazil, are reviewed in this study, which includes the description of a new species of Scartella. The new species differs from its congeners by the combination of the following characters: well-marked diagonal dark line just under the eye, tiny black spots on the head, small black and white spots along the body, 14 segmented dorsal-fin rays, 15 segmented anal-fin rays, and 23 caudal vertebrae. This is the second Scartella species described from Brazilian oceanic islands.