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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[SUB9] and S[SUB11]) 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[SUB9] in Thisoicetrinus pterostichus), two (S[SUB9] and S[SUB10] in Eyprepocnemis unicolor, M[SUB8] and S[SUB11] in Heteracris adspersa), or three (S[SUB9], S[SUB10], and S[SUB11] 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. [ABSTRACT FROM AUTHOR]

Analysis of chromosome localization of three molecular markers, 18S-5.8S-28S rDNA, 5S rDNA and a 180 bp satDNA, showed that B chromosomes in the grasshopper Eyprepocnemis plorans originated independently in Eastern (Caucasus) and Western (Spain and Morocco) populations. Eastern B chromosomes are most likely derived from the smallest autosome, which is the only A chromosome carrying the three markers, in coincidence with Caucasian B chromosomes. Western B chromosomes, however, lack 5S rDNA and are most likely derived from the X chromosome, which is the only A chromosome carrying the two remaining markers, always in the same order with respect to the centromere, as the B chromosome. [ABSTRACT FROM AUTHOR]