Paulo, BraziL Emailfransozo@ibb.IlI.U) Yp.br ABSTRACTThe influence of environmental factors on the abundance and spatial-tempotal distribution of the sltrimp Xiphopenaeus kroyeri was investigated. in southeastern Brazil over 2 years. Monthly collections were conducted in Mar Vrrado, Dbatuba and Dbatumi!im Bays using a commercial shrimp fishing boat equipped with 2 "doubJe.-rig" nets. Each bay was divided into 6 samplJng stations, all of which were less than 25 m deep. The spatial distribution of X kroyeri differed among Bays. Highest abundance values were recorded in areas where silt and clay comprised more than 70% of the bottom sediment Abundance of X kroyeri followed a seasonal trend, heing higher during fall and winter, when intrusions of tropical waters are frequent, causing an increase in salinity (> 35%") and temperature (> 21° C). A clear decrease in shrimp abundance followed a decrease in bottom temperature « 20" C) during spring and summer due to the influence of cold water currents, particularly the South Atlantic Central Water. These results suggest that sediment type, salinity, and temperature are among the most important variables affeclJng the spatial and seasonal distribution of this species.

The in£uence of several environmental factors on the abundance and spatial^temporal distribution of the shrimp Artemesia longinaris were investigated from January 1998 to December 1999 in the Ubatuba region of Sa‹ o Paulo State, Brazil. Collections were performed monthly in the bays of Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV). Six sampling transects were established in each bay, four were parallel to the shore line, and two were next to the rocky shores. A commercial shrimp ¢shing boat equipped with two 'double-rig' nets was used. A total of 11,503 individuals was collected, including 1633 from UBM, 6344 from UBA and 3526 from MV. The majority of the captured specimens came from the deeper areas (15 to 20 m) with high salinity (34 to 36 ppt). The highest abundance of A. longinaris in Ubatuba bay was recorded in areas where ¢ne and very ¢ne sand comprised more than 70% of the sediment. Moreover, the abundance of A. longinaris followed a seasonal trend, being higher during the summer, when intrusions of cold South Atlantic Coastal Waters (SACW) are frequent. Thus, type of sediment, temperature and salinity are determinant factors in the distribution of A. longinaris in the studied region.

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The impact of shrimp fisheries in tropical regions has become comparable to the world's most intensively exploited temperate shelf ecosystems. The increase in the fishing fleet in south-eastern Brazil and the decrease in landings of profitable shrimp species have contributed to the incorporation of additional species into those fisheries. The goal of the present study is to investigate the influence of environmental factors on the abundance patterns of shrimp communities on the south-eastern coast of Brazil, over a period of two years. Monthly collections were conducted in the Ubatuba and Caraguatatuba regions using a commercial shrimp fishing boat equipped with 'double-rig' nets. Each region was divided into 7 sampling stations up to 35 m deep. The relationship between the environmental factors and the abundance patterns in the shrimp communities was assessed using a canonical correlation analysis (CCorrA). The first set of variables used during the CCorrA included environmental characteristics and the second set of variables the abundance of the studied species. A total of 374,915 individuals were collected during the present study. Xiphopenaeus kroyeri showed the highest abundance (273,127), followed by Artemesia longinaris (73,422), and Pleoticus muelleri (15,262). In the first root, depth and temperature showed the highest factor loadings (0.9 and 20.7) and canonical weights (0.6 and 20.4). These environmental factors were strongly associated with the abundance of X. kroyeri (factor loading ¼ 2 0.9 and canonical weight ¼ 2 0.9). The second root demonstrated a positive relationship between abundance of P. muelleri and depth, and an inverse association with bottom temperature. The abundance patterns of X. kroyeri and P. muelleri were strongly affected by the water mass South Atlantic Central Water (cold waters ¼158C), which can lead to a temperature decrease in deeper areas (.15 m). Thus, the opposite abundance trend for depth of these species might reflect bathymetric variation in temperature, a clear example of distinct behavioural differences of species of different origins, either tropical (X. kroyeri) or subantarctic (P. muelleri). The low overall association between environmental parameters and shrimp abundance patterns indicates that each studied species might have responded idiosyncratically to environmental variation, such that a general community-level response was not apparent. However, other confounding factors such as intraspecific migration patterns might have also played a role in generating the observed patterns.

This study aimed to provide an illustrated identification key to distinguish Dendrobranchiata marine shrimps which, occur in the littoral north São Paulo State as deep as to 40m. A total of 13 species were captured using a shrimp fishery boat with two double-rig nets. Monthly trawlings were carried out from 1995 to 2000 in the region of Ubatuba, SP. This key includes the commercial value of species such as the penaeids Xiphopenaeus kroyeri, Farfantepenaeus brasiliensis, F. paulensis, Litopenaeus schmitti, Artemesia longinaris and the solenocerids Pleoticus muelleri. In addition to these species, shrimps that are not of commercial interest were also include such as Rimapenaeus constrictus, Acetes americanus, Peisos petrunkevitchi and the sicionids Sicyonia dorsalis, S. typica, S. laevigata and S. parri. The key proposed here might facilitate the identification of Dendrobranchiata shrimps by a variety of users, including scientific researchers as well as people responsible for making the laws that regulate fisheries, principally in the protection period.Key words: Identification key, Dendrobranchiata, shrimps, São Paulo. ResumoO presente estudo teve como objetivo a elaboração de uma chave de identificação ilustrada para diferenciar as espécies de camarões marinhos Dendrobranchiata, com ocorrência no litoral do Estado de São Paulo até a profundidade de 40m. As 13 espécies apresentadas neste trabalho foram obtidas mediante coletas mensais durante os anos de 1995 a 2000 na região de Ubatuba, SP . Nesta chave estão incluídas as espécies de interesse econômico, como os peneídeos Xiphopenaeus kroyeri, Farfantepenaeus brasiliensis, F. paulensis, Litopenaeus schmitti, Artemesia longinaris e o solenocerídeo Pleoticus muelleri. Além destas espécies, também foram adicionados os camarões que não são alvos das frotas pesqueiras, entre eles, Rimapenaeus constrictus, Acetes americanus, Peisos petrunkevitchi e os sicionídeos Sicyonia dorsalis, S. typica, S. laevigata e S. parri. A chave proposta servirá como uma ferramenta no auxílio da identificação dos camarões Dendrobranchiata, quer seja por pesquisadores ligados à área científica, como também por pessoas relacionadas aos órgãos responsáveis pelo controle da pesca, principalmente, na época do defeso. Palavras

This study records, for the first time, the occurrence of all four male morphotypes in a population of Macrobrachium amazonicum from a continental environment, with an entirely freshwater life cycle. The specimens studied came from the Tietê River, state of São Paulo, Brazil, and were collected in a lotic environment downstream from Ibitinga Dam. This population was compared with other continental populations, including a population from the dam itself, collected in a previous study. Four samples of 30 minutes were taken monthly, using a trap, from January to April 2011. Each male specimen was measured with respect to seven body dimensions as follows: carapace length (CL), right cheliped length (RCL), dactyl length (DCL), propodus length (PPL), carpus length (CRL), merus length (ML) and ischium length (IL). The relative growth was analyzed based on the change in growth patterns of certain body parts in relation to the independent variable CL. The four male morphotypes proposed for the species were found using morphological and morphometric analyses. Different biological characteristics were found between the populations studied. The male population of the lake of Ibitinga and from Pantanal presented mean sizes and number of morphotypes lower than the population studied here. These differences seem to be closely related to ecological characteristics of the environments inhabited by these populations. Our results supported the hypothesis that coastal and continental populations of M. amazonicum belong to the same species.Keywords: freshwater prawn, allometry, Tietê River, Amazon River Prawn, morphotype characterization. Ocorrência de morfotipos em machos de Macrobrachium amazonicum(Caridea, Palaemonidae) em uma população com ciclo de vida completamente dulcícola ResumoEste estudo registra, pela primeira vez, a ocorrência dos quatro morfotipos de Macrobrachium amazonicum em uma população continental com ciclo de vida totalmente dulcícola. Os camarões são provenientes do Rio Tietê, estado de São Paulo, Brasil, e foram coletados em um ambiente lótico abaixo da Barragem de Ibitinga. Essa população foi comparada com outras populações provenientes de ambientes continentais, incluindo a de um estudo anterior na represa da barragem de Ibitinga. Quatro amostras de 30 minutos foram realizadas mensalmente, utilizando armadilhas, de janeiro a abril de 2011. Cada indivíduo macho foi mensurado em relação a sete dimensões corporais, sendo elas: comprimento da carapaça (CL), comprimento total do quelípodo direito (RCL), comprimento do dáctilo (DCL), comprimento do própodo (PPL), comprimento do carpo (CRL), comprimento do mero (ML) e comprimento do ísquio (IL). O crescimento relativo foi analisado de acordo com as mudanças nas taxas de crescimento de determinadas partes do corpo em relação à variável independente CL. Os quatro morfotipos descritos para a espécie foram encontrados, utilizando análises morfológicas e morfométricas. Diferentes características biológicas foram encontradas entre a população estudada e as demais...

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