INFLUENCE OF DIET ON SURVIVAL AND DEVELOPMENT OF Notodiaptomus cearensis WRIGHT, 1936 (CRUSTÁCEA: COPEPODA) AND Physiocypria schubarti FARKAS, 1958 (CRUSTACEA: OSTRACODA)

• Autor(a) principal: Câmara, Fabiana Rodrigues de Arruda
• Data de Publicação: 2014
• Outros Autores: Pessoa, Emilly Kataline Rodrigues, Santos, Leila Laise Souza, Rocha, Odete, Chellappa, Sathyabama, Chellappa, Naithirithi Tiruvenkatachary
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Biota Amazônia
• Texto Completo: https://periodicos.unifap.br/index.php/biota/article/view/795

The Ostracod and Copepod are dominant groups of zooplankton in freshwater eutrophic ecosystems. The high abundance of Ostracod coincides with the significant reduction of the Calanoid Copepod biomass, co-existing with filamentous cyanobacterial blooms. The present study based on experimental set up, aimed to test survival, growth and development of the species Notodiaptomus cearensis Wright, 1936 (Calanoid Copepod) and Physiocypria schubarti Farkas, 1958 (Ostracod) and to interpret the possible relationships between Copepod and Ostracod in natural waters. Two experimental tests were performed using the Armando Ribeiro Gonçalves (ARG) reservoir raw water. For the first series of test, the species Ceriodaphnia dubia was used as test-organism to verify the toxicity tolerance presumed to be in the raw reservoir water and to record how the growth and development of Copepod and Ostracod occur in this condition. The second test was conducted using the species N. cearensis and P. schubarti in order to observe a possible resource competition between these two species. The outcome of the results showed an inverse relation of biomass of Ostracod and Calanoid Copepod.  Two types of growth pattern were observed: 1) The Ostracod, P. schubarti growth rates are relatively constant regardless of the different types of food supply and 2) the copepod, N. cearensis, though it grows when fed with filamentous cyanobacteria, and exhibited preferential uptake of green algae food. Therefore, the outcome of the results did not support the hypothesis of resource based competition while taking into consideration ample seasonal variation of the species N. cearensisand P. schubartiand their continued co-existence in the water column. Conclusion may be drawn from the fact that P. schubarti did not affect the growth of N. cearensis, the reduction of density of N. cearensis probably due to factors inherent survival ability in the midst of high density Ostracod or presence of filamentous cyanobacteria. It can be inferred that the cyanobacterial toxicity may affect some individuals in the population of N. cearensis and Ceriodaphnia dubia when exposed to filamentous cyanobacteria. Keywords: Zooplankton; Toxicity; Semiarid.