Endopolyploidy dynamics in the cerebral ganglion development of Solenopsis saevissima (Smith, 1855) (Hymenoptera, Formicidae)

Endopolyploidy, the presence of cells with multiple sets of chromosomes, is a phenomenon observed in various insect tissues. These cells can arise through endoreplication or endomitosis, processes that lead to increased DNA content without cell division. In this study, we investigated, for the first time, the occurrence of endopolyploidy in the different developmental stages (larvae, young and old prepupae, pupae, and adults) of Solenopsis saevissima. Using flow cytometry, we measured the DNA ploidy levels and observed the presence of 2C, 4C, and 8C nuclei throughout the developmental stages. Our findings revealed dynamic changes in the mean number of 2C, 4C, and 8C nuclei during S. saevissima’s developmental stages, with a gradual decrease in endopolyploid cells (4C and 8C) over time. Cytogenetic analysis confirmed the presence of tetraploid cells alongside diploid cells in the cerebral ganglion, suggesting that endomitosis promotes endopolyploidy in the cerebral tissues of S. saevissima. These findings highlight the changes in endopolyploidy levels within cerebral ganglion cells throughout the developmental stages of S. saevissima and provide insights into its potential implications for the biology of fire ants. Further research is needed to fully understand the genetic and metabolic effects of endopolyploidy in these organisms.