Cytogenetic variability of the genus Saga Charp. (Orthoptera, Tettigoniidae, Saginae): heterochromatin differentiation

Chromosome complements of Saga hellenica, S. natoliae, and S. rhodiensis consist of 2n = 28 + XO in males and 2n = 28 + XX in females (FN = 32 and 34, respectively), Robertsonian fusions and tandem fusion play the most important role in the evolution of the chromosome set in Saginae. The chromosomes of three species of Saginae were analyzed by four different staining methods: C-banding, Ag-NOR, DAPI and CMA(3). The studied species show a uniform karyotype with differences in constitutive heterochromatin content. C-banding patterns plus fluorochrome staining shows differences between paracentomeric, interstitial, and telomeric segments, as well as the hererochromatin associated with NORs.