Abstract The Indo-Pacific edible swimming crab Scylla serrata is reported here for the fifth time from the western Atlantic including a failed attempt of introduction to Florida for aquaculture purposes in the years 1960’s. The species had been recorded from Brazil in the early 1980’s and in 2011 and from the Caribbean coast of Colombia in 2013. The capture of a third specimen in southeastern Brazil on 24 August 2020 is discussed here. On all occasions individuals found in Brazil were adults captured alive near port areas. The occurrence of S. serrata in disparate time periods in the western Atlantic (1983, 2011, 2013 and 2020) is regarded as an indication of low inoculation pressure.

Abstract The Indo-Pacific swimming crab Charybdis hellerii (A. Milne-Edwards, 1867) is native to the Indo-Pacific Ocean, and occurs as an invasive species along the Eastern American coast, where it was probably introduced in ballast water. The present study evaluated the osmoregulation and salinity tolerance of C. hellerii in Paranaguá Bay, Paraná, Brazil, an estuary under the constant threat of introduction of non-native species. The crabs were abruptly submitted to salinities of 10, 20, 30 (control), and 40 PSU for 24h. Hemolymph osmolality showed either an increase or a decrease following the changes in water salinity, presenting a pattern of hyper-osmoconformation. Muscle water content was stable at salinities from 20 to 40 PSU, and increased after exposure to 10 PSU indicating cellular swelling. At 10 PSU a physiological limit was reached, indicated by the failure of the capacity to regulate tissue water content. Although adult C. hellerii tolerate a wide range of salinities for 24 h, its osmoregulatory ability indicates a possible advantage for its establishment in estuarine waters with salinities <20 PSU. The salinity tolerance and osmoregulatory data are important basic information to be used in models to predict and prevent the invasion of the species into new areas of the Neotropics.

O camarão-barba-ruça (Artemesia longinaris) e o camarão-santana (Pleoticus muelleri) são espécies que sustentam uma pescaria responsável por elevadas capturas das frotas de camaroeiros no sul do Brasil. Este trabalho teve como objetivo analisar a variabilidade da abundância das duas espécies à variação dos dados de DPUEs da frota de arrasteiros em operação entre 1998 e 2005, por meio do ajuste de Modelos Lineares Generalizados (MLG). As principais variações de abundância das duas espécies estão relacionadas aos ciclos anuais e a temporada de pesca. As áreas rasas ao sul do Rio Grande do Sul proporcionaram maiores rendimentos. Não foram observadas tendências de aumento ou declínio na abundância do estoque, mas o esforço de um determinado ano é condicionado pelo sucesso das capturas do ano anterior. Nos dois últimos anos analisados a abundância e as capturas totais foram reduzidas.

The Argentine stiletto shrimp (Artemesia longinaris) and the Argentine red shrimp (Pleoticus muelleri) currently sustain an important fishery in terms of tonnage and revenues in southern Brazil. This study analyzed the factors affecting the abundance of both species through the application of Generalized Linear Models to landing-per-unit-of-effort (LPUE) data of the trawl fleet operating on the main fishing grounds between 1998 and 2005. The main patterns of LPUE variability of both species were attributed do the effect of seasons and annual cycles. Larger yields were obtained in the southern shallow areas of Rio Grande do Sul State. No tendency either to an increase or a decline in stock abundance was observed, but the effort in one year was affected by the success of the captures of the previous year. In the last two years analyzed the abundance and the total captures declined.