Detailed karyotyupe information (the number, C-bands, NORs) of Tetigonia cantans, T.viridissima, T.caudata, and T.ussarina is given.Differences in mean chasma frequency and in the position of C-bands between species are discussed.
Karyotypes and C-heterochromatin distribution of Deracanthina deracanthoides, Deracanthella verrucosa and Zichya baranovi were studied. Differences in the chromosome numbers, their morphology, and the position of C-bands between species of Bradyporinae are discussed.
Chromosome numbers and C-banding patterns in the spermatogenesis of seven species of Pamphagidae grasshoppers from the Caucasus, Central Asia, and Trabsbaikalia region of Russia are reported. The patterns of origin and evolution of the neo-XY/neo-XX sex determination in Pamphagidae are discussed.
The randomamplified polymorphicDNA(RAPD-PCR)methodwas used to study the genetic polymorphism of 20 species of the genus Isophya. Each primer amplified a different set of DNA fragments, all oligonucleotides failed to generate any specific diagnostic band that could lead to the identification of Isophya species, and none of the amplified fragments were present in all species. RAPD markers detected a high level of polymorphism in all species. The data were in most cases not congruent with morphological subdivision to the species group and cytotaxonomic studies. The genetic lin with relationships proposed by systematists.
The C-banding patterns in the embryo chromosomes of the grasshopper Podisma pedestris (L.) from the Altai Mts are reported. The additional second C-heterochromatic arms in at least five pairs of autosomes and in the X-chromosome were revealed. The paracentromeric, interstitial, and telomeric C-bands were observed. The studied population of P. pedestris shows some differences in the distribution and amount of the heterochromatin in comparison with European populations.
So far, only about 400 species, subspecies, and chromosome races of 15 subfamilies of Tettigoniidae have been studied karyologically, this constituting about 7% of all described species in this group. An attempt was made to establish the basic diploid chromosome numbers of Tettigoniidae and, considering chromosome number, morphology, and the sex determining mechanisms, to suggest how karyotype evolution in the particular subfamilies could have occurred.
A method of grasshopper embryo karyology was adopted for Tettigoniidae. Additionally, detailed information of the C-banding pattern of embryos of Tettigonia cantans from the Novosibirsk population is given.
Detailed karyotype information (the number, shape, C-bands, NORs, and chiasmata) of Tachycines coreanus Yamasaki, 1969 from South Korea is given for the first time. The karyotype of this species with 2n male=49 (XO) possesses all acrocentric chromosomes.
Heteromorphism of distal C-bands of differnet origin connected with the M2 bivalent was observed in four analysed species, i.e.Tettigonia cantans, Tettigonia viridissima, Tettigonia caudata and Tettigonia ussuriana.Study of the chiasma distribution showed that presence of heteromorphic segments significantly modified this pattern, and hiasma formed preferentially in the chromosomal region furthest from the heteromorphic segment.Additionally, in the M3 bivalent of Tettigoni cantans, in the L1 of Tettigonia viridissima, and in the X chromosome of Tettigonia cantans, Tettigonia viridissima and Tettigonia caudata variability of the distal segment was observed.
Karyotypes and C-banding patterns of four species belonging to three genera of the subfamily Phaneropterinae were studied. The basic karyotype of Isophya kalishevskii, Polysarcus zacharovi, and Poecilimon ukrainicus consists of 2n=31(XO) in the male. The chromosome number of Isophya hemiptera is 2n%=28+neo-X+neo-Y as a result of mutual tandem translocation between the originally acrocentric X-chromosome and acrocentric medium size autosome. Analysis of the meiotic behaviour of the neo-X and neo-Y demonstrated a post-reductional division of these chromosomes.
Karyotypes (the number, shape, C-bands, NORs, chiasma frequency) of four species of Landrevinae were studied. Three species are characterized by a karyotype of 2n male=19 - Duolandrevus (Eulandrevus) sonorus, D. (E.) dendrophilus and D. (E.) enatus while Vasilia vietnamensis showed 2n=17. Differences of karyotypes are connected with simple Robertsonian translocation in autosomes. Successive stages of spermatogenesis were analysed.
Karyotypes (chromosome number and shape) of four species of the subtribe Liarina were studied. The chromosome numbers and NF (Fundamental Number) in this group of species range from 2n%=33 (34) to 27(30): Liaromorpha buonluoiensis 2n%=33 (34), Sialaiana transiens 2n%=29 (34), Liara tramlapensis 2n%=29 (32), and Anelytra (Perianelytra) propria 2n%=27 (30). Cyto-taxonomy analysis indicates an intensive karyotype evolution among species belonging to three different groups of the genera. Differences of karyotypes are connected with Robertsonian fusion and tandem fusion in autosomes. Additionally, C-banding distribution and location of the NORs were studied.
The C-stained karyotypes of five species of three dragonfly families from Western Siberia and Kunashir Island have been analysed. Gomphus epophtalmus Sel., G. vulgatissimus (L.), Nihonogomphus ruptus (Sel. et Hag.) (Gomphidae), and Anotogaster sieboldii (Sel.) (Cordulegasteridae) showed usual character of C-heterochromatin distribution, all chromosomes have terminal C-bands. Somatochlora graeseri Sel. (Corduliidae) has unique for dragonflies type of terminal C-blocks on autosomes. Three pairs of autosomes have the very large heterochromatic blocks, other chromosomes, including the X, have no C-band.
Karyotypes and meiosis of Glomeris hexasticha and G. connexa (Diplopoda: Glomeridae) from Poland were described using C-heterochromatin distribution and observations of the location of NORs. These species were characterized by 2n>=16 and the XY sex determination system. Differences were found in the amount of C-heterochromatin in X and Y chromosomes between the studied species. In G. hexasticha, supernumerary B chromosomes were described.
The karyotype of Apteranabropsis tonkinensis, described for the first time, is characterized by 2n_= 19 (XO) and 2n_=20 (XX). Successive stage of spermatogenesis were analysed.
Karyotypes, C-bands distribution of nine species belonging to 6 genera, and chromosomal location of NORs in some species were studied. Differences in the chromosome numbers, their morphology, and the position of C-bands between species of Poecilimon and IIsophya are discussed.
Tettigonia ussuriana and T. dolichopoda maritima differ in the length of tegmina, details in venation, and in females in details of the subgenital plate. The two species of the genus Tettigonia have the same number and morphology of autosomes but a different morphology of the X chromosome: in T. ussuriana it is metacentric, whereas in T. dolichopoda maritima acrocentric. In both species, euchromatic zones and breaks of one or to chromatids during meiosis and mitosis in theXchromosome were observed. Additionally, B chromosomes were noted in most individuals of both species.
Seven categories of B chromosomes found in the brachypterus grasshopper Podisma sapporensis from Hokkaido populations differ in structure, size, and C-band content. The interchange between B and one autosome from M3 and sporadically M7 was observed in most of the populations examined. Such an interaction between standard and non-standard chromosomal set provides an insight into the integration of supernumerary chromosome. In addition, C-heterochromatin polymorphism was also identified in male karyotypes in some populations. These facts indicate P. sapporensis is a highly polymorphic species from the cytogenetic point of view.
Karyotypes and C-banding patterns of grasshoppers, members of the subfamily Eypre- pocnemidinae Thisoicetrinus pterostichus (F.-W.), Heteracris adspersa (Redt.), Eypre- pocnemis unicolor Tarb., Eyprepocnemis plorans (Charp.), and Shirakiacris shirakii (I. Bol.) are described. Chromosome complements of these species are composed of 23 acro- centric chromosomes in the male. The sex-determining mechanism is X0_/XX_. The B chromosomes were observed in the Northern Caucasus population of E. plorans. There was no evidence for any significant effect of 2Bs on either mean chiasma frequency or between cell-variance. There was a significant increase in the mean chiasma frequency for specimens with 1B.
The results of experimental hybridisation between some chromosome subraces belonging to the X0 and XY chromosome races of the brachypterous grasshopper P. sapporensis are presented. Pre-zygotic reproductive isolation mechanisms in experimental pairs were not confirmed. In crossings of XY-standard x X0-standard and XY-standard x X0-Naganuma chromosome subraces, a zygotic barrier has been found. All embryos of XY-standard x X0-standard crosses and the vast majority of embryos of XY-standard x X0-Naganuma crosses were obtained from female diploid or haploid/diploid cells as a result of parthenogenesis. In very rare cases, when the zygotic barriers had been surmounted, normal embryo heterozygotes and a F1 hybrid generation were obtained in XY-standard x X0-Naganuma crosses. On the contrary, crosses between the XY-Tanno and X0-standard subraces gave viable offspring in spite of many chromosome differences such as a X-A translocation and fixed pericentric inversions in four pairs of autosomes. The results obtained do not support the hypothesis that chromosomal differences play a key role in restricting gene flow between X0 and XY races of P. sapporensis. The presence of crossing barriers explains the phenomena of the purity of the X0 and XY chromosomes races.
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