Comparative FISH analysis in five species of Eyprepocnemidine grasshoppers

The chromosomal localization of ribosomal DNA, and a 180 bp satellite DNA isolated from Spanish Eyprepocnemis plorans specimens, has been analysed in five Eyprepocnemidinae species collected in Russia and Central Asia. Caucasian E. plorans individuals carried each of the two DNAs, but the rDNA was limited to only two chromosomes (S-9 and S-11) in sharp contrast to Spanish specimens that show 4-8 rDNA clusters and to Moroccan specimens which carry rDNA in almost all chromosomes. The four remaining species, however, lacked the 180 bp tandem repeat, and showed rDNA clusters in one (S-9 in Thisoicetrinus pterostichus), two (S-9 and S-10 in Eyprepocnemis unicolor, M-8 and S-11 in Heteracris adspersa), or three (S-9, S-10, and S-11 in Shirakiacris shirakii) chromosome pairs. The implications of these findings for the evolution of these two chromosome markers in this group of species are discussed.