“…Heterochromatic B chromosomes, as visualized in B. westermanni , have already been reported in karyotypes of other species of Pimelodidae [Borin and Martins-Santos, 2004;Carvalho and Dias, 2005]. The presence of only 1 NOR-bearing chromosome pair is the most common condition among the pimelodids [Borin and Martins-Santos, 2002;Treco and Dias, 2009;Carvalho et al, 2010;Swarça et al, 2013], and the correspondence between CDD sites and NORs, observed in this study, has already been found in the genomes of other species of this family [Garcia and Moreira Filho, 2005;Swarça et al, 2005Swarça et al, , 2013Treco et al, 2008;Carvalho et al, 2011]. The location of (TTAGGG) n sites only in telomeric regions indicated the complete lack or a small number of chromosomal rearrangements of translocation/fusion types.…”