ABSTRACT. Spatial and temporal dynamics of Brachyura zoeae (Crustacea, Decapoda) in the Jaguaribe river estuary, Itamaracá, Pernambuco, Brazil. A survey regarding the diel and seasonal distribution of brachyuran zoea was accomplished in the Jaguaribe estuary, state of Pernambuco, Brazil. Plankton samples were obtained bimonthly, throughout the year of 2001, in different tides and during day and night periods, at two sampling stations. Fourteen taxa were identified, among which Ocypodidae, represented by Ucides cordatus (Linnaeus, 1763) and Uca spp. zoea, was the most abundant one, followed by Xanthidae and Grapsidae. In the station close to the estuary opening, the taxa were well distributed, besides presenting a larger number of identified families. Ocypodidae, Grapsidae and Morphotype B zoea indicated a dispersion movement into coastal areas, while Pinnotheridae indicated a probable retention within the estuarine waters. The high occurrence of zoea in the first larval stages reinforces the important role of estuaries as nursery grounds for several crustacean species.

Molidae are tropical marine teleosts that occur in all oceans. Among the species described, Masturus lanceolatus is considered rare on the Brazilian coast, with only four records found in scientific publications. The present study reports the first occurrence of this species for the coast of the State of Pernambuco (north-eastern Brazil) and discusses the possible causes of its being stranded. The specimen was found alive in the estuary of the Una River in the city of São José da Coroa Grande on the southern coast of the state. The fish was unknown to the local community of fishermen, who considered it a 'bad omen'. The occurrence led to an environmental education project in the community carried out by members of the Tropical Marine Ichthyology Group, which carried out an inspection, documentation, analysis of external injuries and collection of viscera for the subsequent histological analysis. After undergoing taxidermy, the specimen was donated to the Una Museum. Analysis revealed that the fish suffered from an intense inflammatory process of the liver caused by polycystosis of nematodes and Trypanorhyncha, which resulted in malnutrition, as observed by the low body weight. Moreover, a likely stranding left the specimen more vulnerable to different species of shark, which mutilated it, hindering its locomotion. This fish appears to have drifted and was thrown against the reefs near the estuary before its stranding.

The genusAchirusis made up of demersal fish that have a close relationship with the substrate and exhibit peculiar aspects during their larval stage. The aim of the present study was to determine whether the abundance ofAchiruslarvae differed among a set of habitats in the estuary of the Formoso River in the State of Pernambuco (north-eastern Brazil). Sampling was performed monthly between April 2009 and March 2010, and comprised horizontal hauls with plankton net during the day and night in mangrove, beach and reef habitats. Fish larvae were sorted, identified, measured and larval stage recorded. Density and body length values were used in a non-parametric analysis of variance for the determination of variations between seasons, habitats and diel periods. A total of 204 larvae were collected, with an average density of 2.1 larvae.100 m−3. Density was greater in the nocturnal samplings, with no differences found between habitats. The larvae occurred in the yolk-sac to post-flexion stage, with pre-flexion the most abundant stage (78%). Size segregation was observed. Larger larvae were captured at night and in the mangrove. The smallest larvae were caught on the reef, with length increasing toward the mangrove. The results indicate thatAchiruslarvae come from deeper regions near reefs, where spawning probably occurs, and perform ontogenetic migration towards the shallow waters of mangrove, where they settle.

ABSTRACT. The present study aims to compare the buccal apparatus and gastrointestinal tract of early life stages of Centropomus undecimalis (Bloch, 1792), and relate them to its diet. A total of 190 individuals collected with a channel net in the Catuama estuary (07°40'9.9''S, 34°50'36.7''W), northern coast of the state of Pernambuco, were examined. Morphometrical and meristic data were analyzed for the two initial developmental periods (larval and juvenile). Their digestive tube was morphologically characterized and its content identified. The longest transverse axis of food items was measured, and compared to the standard length (SL) and mouth gape size (D) of the individuals. Body measurement regressions differed significantly (p<0.001) between larvae and juveniles. The stomachs with food content (n=118 individuals) presented a proportion of 62% full and 30% empty (being 8% damaged). They differed in relation to the fullness level and presented a coiled shape when empty. The number of food items in relation to SL and D did not present an evident correlation. Larvae (SL<10 mm) feed on small copepods, while juveniles (SL=11.1 to 64.7 mm) ingest larvae of various decapod species, showing a distinct diet between these initial developmental stages.

Neste estudo se ressalta a alimentação natural de larvas do peixe-rei Atherinella brasiliensis (Atherinopsidae) coletadas no estuário do Rio Jaguaribe, Itamaracá, Pernambuco, ressaltando-se que o conteúdo gastrintestinal de 98 indivíduos, coletados mensalmente ao longo do ano de 2001 com rede de plâncton cônico-cilíndrica e malha de 500 mm de abertura, evidenciou que a espécie apresenta hábito alimentar oportunista em suas fases larvais, ou seja, sua dieta depende da disponibilidade local de alimento. Tintinnina foi o item alimentar dominante, presente em 23,5% das larvas com conteúdo gastrintestinal, seguido das Copepoda e Microalgas; outros itens, como Trichodina sp. (Protozoa), ovos de invertebrados e organismos não identificados, também representaram itens significativos na dieta das larvas. Palavras-chave:Tintinnina, Favella, larvasdepeixe, hábito oportunista Feeding in early life stages of the Brazilian silversides Atherinella brasiliensis (Atherinopsidae) from the Jaguaribe River estuary, Itamaracá, PE ABS TR A CT Natural feeding of Atherinella brasiliensis (Atherinopsidae) larvae, collected in the Jaguaribe River Estuary, Itamaracá-Pernambuco, was studied. Gastro-intestinal contents of 98 individuals, collected at monthly interval during the year 2001, with a 500 mm mesh size conical-cylindrical plankton net, showed that early life stages of this species presents an opportunistic feeding habit, i.e. its diet depends on local food availability. Tintinnina was the most frequent food item, present in 23.5% of the larvae with gastro-intestinal content, followed by Copepoda and Microalgae. Others items, such as Trichodina sp. (Protozoa), invertebrate eggs and unidentified organisms also represented important items in the diet of A. brasiliensis.