Differentiated evolutionary pathways in Haemulidae (Perciformes): karyotype stasis versus morphological differentiation

Extensive phenotypic diversity (size, colors and shapes) among species of Haemulidae is practically dissociated from the conservative cytogenetic pattern observed in this family. Detailed analyses indicate that karyotypic stasis is maintained even under the scrutiny of different chromosome investigation methods. Chromosomal banding patterns (endophenotype) of five Atlantic species are presented here: Conodon nobilis, Pomadasys corvinaeformis, Haemulon aurolineatum, H. plumierii and H. steindachneri, obtained by incorporating the base analog 5-BrdU, C-banding and staining with base-specific fluorochromes. Despite a few chromosomal specificities, relative karyotypic conservation was confirmed, corroborating earlier studies on this family. On the other hand, phenotypic patterns (exophenotype), identified by geometric morphometrics contrast visibly with the chromosomal conservation of this group. As such, the evolutionary rates of chromosomes and body morphology demonstrate clear asynchrony. Possible causes of karyotypic stasis in Haemulidae are discussed as well as the sharing of this condition with other Perciformes.