Diversity and spatial-temporal distribution of caridean prawns larvae and adults in the lower basin of the Ribeira de Iguape River (SP)

Abstract

There is little systematic information on freshwater decapods at coastal basins of southern coast in the São Paulo state, where the Ribeira Valley is one of the priorities of the environmental viewpoint. Furthermore, knowledge about the composition, density and / or spatial-temporal distribution of caridean prawn larvae is virtually nonexistent, which hinders access to the knowledge about the life cycle of the species. So the purpose of this project is to conduct a study in order to interact the larval and adult ecology of estuarine and freshwater caridean from the lower basin of Ribeira de Iguape River, including the Valo Grande channel, Iguape municipality (SP). This study includes species diversity, abundance and identification of larvae in the plankton through DNA analysis, the association of environmental parameters with the spatial-temporal distribution of the adults and larvae and aspects of population biology. Samplings will be held for twelve months in three areas of the lower Ribeira de Iguape River, using traps and sieves for adults and juveniles and a plankton net for larvae. The prawns will be separated by gender and measured for the analysis of population structure. The prawn larvae will be identified at the species level using DNA. To highlight differences in the abundance of prawn larvae and adults among the seasons of year and sample sites, an ANOVA will be conducted, and multivariate techniques will be used to associate prawn abundance with environmental parameters. The results of this project will add data to the little existing amount of knowledge in the region about adult, juvenile and larvae of caridean prawns, which are organisms of high ecological and economic importance. (AU)