Life history traits and secondary production of Campsurus violaceus (Ephemeroptera: Polymitarcyidae) in the Paraná River floodplain lakes, Argentina

Abstract

Campsurus nymphs are among the most abundant mayflies in neotropical aquatic habitats. The abundance patterns and secondary production of Campsurus violaceus were analyzed monthly from April 2005 to March 2006 in lakes with different degrees of connectivity in the floodplain of the Middle Paraná River. Significant differences were estimated for the abundance and secondary production of the species among the studied lakes. The patterns in the abundance of nymphs were correlated to substrate characteristics (type of substrate, content of detritus), water transparency, and conductivity of lakes and the variations in the life cycle were related to temperature. Degree of connectivity of lakes was the main factor in determining differences among populations, as it influenced local conditions, finally determining regional dissimilarities in abundance pattern and secondary production for the species.