[1] Royal Belgian Inst Nat Sci, Freshwater Biol, Vautierstr 29, B-1000 Brussels, Belgium
[2] Univ Ghent, Dept Biol, KL Ledeganckstr 35, B-9000 Ghent, Belgium
[3] State Univ Maringa UEM, Ctr Biol Sci CCB, Dept Biol DBI, Grad Program Ecol Inland Water Ecosyst PEA, Av Colombo 5790, BR-87020900 Maringa, PR, Brazil
[4] State Univ Maringa UEM, Ctr Biol Sci CCB, Ctr Res Limnol Ichthyol & Aquaculture Nupelia, Av Colombo 5790, BR-87020900 Maringa, PR, Brazil