Eleven species of Ponerinae ants belonging to six distinct genera, from the Amazon and Atlantic rainforest, were characterized through karyotype, distribution of 45S ribosomal genes, microsatellites (GA)n and telomeric repeats (TTAGG)n. This is the first study mapping microsatellite in Ponerinae ants. Karyotypes ranged from 2n=12 to 2n=94. Colonies of Neoponera verenae from the Amazon (n=31) and Atlantic (2n=40) rainforests, reinforced the hypothesis of a species complex within this taxon. Neoponera globularia workers had 2n=21, including an unpaired large metacentric. Neoponera unidentata workers showed either 2n=12 chromosomes, all metacentrics, or 2n=13 chromosomes, with two acrocentrics and one unpaired metacentric chromosome. The rearrangements involved are discussed with the help of telomeric (TTAGG)n data. All analyzed species had a single pair bearing rDNA clusters, located in the pericentromeric region in most of them. The distribution of (GA)n microsatellite contrasted with the AT-rich chromatin and supported the occurrence of chromosome fissions and the subsequent expansion of constitutive heterochromatin in Ponerinae, in addition to inversions in some species. The chromosomal rearrangements discussed here contribute to our understanding of the mechanisms underlying karyotypic evolution in Ponerinae. This study further underscores the important role of cytogenetics in unraveling the taxonomic characteristics of complex groups.
Nobre et al. (Wed,) studied this question.