SPECIES-SPECIFIC ARCHITECTONICS OF GENERA TIVE TISSUES CHROMOSOMES AND PROBLEMS OF PHYLOGENETIC-RELATIONSHIPS WITHIN THE MELANOGASTER SPECIES SUBGROUP OF THE GENUS DROSOPHILA (SOPHOPHORA)

An analysis was carried out of the peculiarities of interlocation of p rimary ovarian trophocyte polytene chromosomes of Drosophila sechellia in comparison with seven earlier-described species of the melanogaste r subgroup. Based on the data from this analysis and earlier-known res ults of reconstruction of the subgroup phylogeny, the following trend in the evolution of the architectonics of trophocyte chromosomes is su ggested: from a local tight chromocenter (D. orena), to a diffuse chro mocenter (D. erecta, D. simulans, D. sechellia), to its complete disap pearance (D. yacuba, D. mauritiana), and to tight binding of chromosom es to the nuclear membrane (D. teissieri, D. melanogaster).