Abundância das larvas de Porcellanidae (Decapoda, Anomura) no meroplâncton do estuário do Rio Caeté, estuário amazônico brasileiro

Antonio Sérgio Silva de Carvalho, Andréia Barbosa das Nevis, Danielly Brito de Oliveira, Jussara Moretto Martinelli-Lemos

Resumo


The porcelain crabs (Infraorder Anomura) occurs in great abundances between boulders in the intertidal zone of Pará coast, Amazon estuarine region, Brazil. The life cycle of this species includes only two zoeal stages, which are distinctive by their very elongate rostral and posterolateral carapace spines, and are commonly found in estuarine meroplanktonic samples. The present study provides information about the abundance of porcellanid larvae at an estuarine system in the Amazon coastal zone, aiming to understand their distribution in relation to some physicochemical variables: seasonal, diel, tidal and lunar cycles, temperature and salinity. Zooplankton samples were collected monthly from April 2000 to April 2001 with a conical net with 300 μm of mesh size, by horizontal hauls, in the Caeté River estuary, Pará, Brazil. Only zoeal stages of porcellanid larvae were found. In general, their abundance was greater in dry season in relation to rainy season, and flood tide in relation to ebb tide. Greater densities were also registered at higher degrees of salinity. The other variables, moon phases, diel cycle and temperature, had not a significant influence on porcellanid larval abundance in the Caeté River estuary.

Texto completo:

PDF


DOI: http://dx.doi.org/10.14210/bjast.v17n2.p7-15

(eISSN: 1983-9057, ISSN: 1808-7035)