Karyotypic study of five Lutjanid species using conventional and Ag-NORs banding techniques

Resumo

The first cytogenetic comparisons of five snapper species from Thailand were presented here. Renal cell samples were taken from blacktail snapper (Lutjanus fulvus), five lined snapper (L. quinquelineatus), dory snapper (L. fulviflamma), brownstripe red snapper (L. vitta), and mangrove red snapper (L. argentimaculatus). The mitotic chromosome preparation was prepared directly from kidney cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results exhibited that all five snapper species have the diploid chromosome numbers of 2n = 48 and the fundamental numbers (NF) of 48. The presences of large, medium, and small telocentric chromosomes were 22-24-2, 24-20-4, 36-10-2, 28-16-4 and 36-10-2, respectively. The Ag- NORs banding technique provides the pair of nucleolar organizer regions (NORs) at subcentromeric region of the long arm of the respective telocentric chromosome pairs 9, 1, 3, 4 and 9. Their karyotype formulas is as follows: L. fulvus (2n = 48): L₂₂^t + M₂₄^t + S₂^t, L. quinquelineatus (2n = 48): L₂₄^t + M₂₀^t + S₄^t, L. fulviflamma (2n = 48): Lt36 + Mt10 + St2, L. vitta (2n = 48): L₂₈^t + M₁₆^t + S₄^t, and L. argentimaculatus (2n = 48): L₃₆^t + M₁₀^t + S₂^t.