Spatio-temporal variability in the Cladocera assemblage of a subtropical hypersaline lagoon

Abstract Cladocera represent an important zooplankton group because of their seasonal prominence in terms abundance and contribution controlling primary production (phytoplankton). On a global scale, there are few studies on hypersaline environments. The present work aims to evaluate the spatio-temporal variation assemblage across salinity gradient habitats Araruama Lagoon. Samples were collected random months over period four years at 12 fixed stations Lagoon using WP2 plankton net equipped with flow meter. Our results do not reveal significant influence tide as factors affecting assemblage. Five species found Lagoon, only 11 where they reached average 1,799 ± 3,103 ind. m-3. mean Shannon Diversity Index was 0.45 0.2. that stood out frequency were: Penilia avirostris (frequency occurrence: 71%), followed by Pseudevadne tergestina (41%). same also relative abundance, (87%) (11%). absence innermost parts lagoon suggests entrance these locations is possibly inhibited temperature lagoon, being main influencing dynamics assemblages.