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Cytogenetic analysis in the spermatogenesis of Triatoma melanosoma (Reduviidae; Heteroptera)
(2008-07-30)
Triatomines are of great concern in public health because they are vectors of Chagas' disease. This study presents an analysis of the species Triatoma melanosoma. The cytogenetic characteristics of triatomines include ...
Evaluating the karyotypic diversity in species of Hyla (Anura, Hylidae) with 2n = 30 chromosomes based on the analysis of ten species
(2005-07-25)
Ten species of Hyla with 2n = 30 from Brazilian fauna were analysed cytogenetically. Hyla minuta is the unique presenting all bi-armed metacentric or submetacentric chromosomes in the karyotype, therefore, with the highest ...
Isochromosome Y in an infertile heifer
(1990-11-23)
Origin of B chromosomes in Characidium alipioi (Characiformes, Crenuchidae) and its relationship with supernumerary chromosomes in other Characidium species
(Pensoft Publ, 2017-01-01)
B chromosomes are apparently dispensable components found in the genomes of many species that are mainly composed of repetitive DNA sequences. Among the numerous questions concerning B chromosomes, the origin of these ...
Chromosomal Mapping of Repetitive DNAs in Characidium (Teleostei, Characiformes): Genomic Organization and Diversification of ZW Sex Chromosomes
(Karger, 2015-01-01)
The speciose neotropical genus Characidium has proven to be a good model for cytogenetic exploration. Representatives of this genus often have a conserved diploid chromosome number; some species exhibit a highly differentiated ...
Study of chromosomal and nucleolar aspects in testes of Nysius californicus (Heteroptera: Lygaeidae)
(2007-05-18)
In Nysius californicus (family Lygaeidae, subfamily Orsillinae), a pest commonly known as the seed bug, the chromosome complement is 2n = 16 (12A + 2m + XY), testes are formed by seven seminiferous tubules covered by an ...
Unusual occurrence of a ZZ/ZW sex-chromosome system and supernumerary chromosomes in Characidium cf. fasciatum (Pisces, Characiformes, Characidiinae)
(Kluwer Academic Publ, 1998-01-01)
Individuals of two populations of the fish Characidium cf. fasciatum were cytogenetically studied and showed a basic diploid number of 50 chromosomes. Some fishes were found to have 51 to 54 chromosomes due to the presence ...
Heteropicnotic chromatin and nucleolar activity in meiosis and spermiogenesis of Limnogonus aduncus (Heteroptera, Gerridae): a stained nucleolar organizing region that can serve as a model for studying chromosome behavior.
(2008-12-01)
Males of Limnogonus aduncus were found to have the sex chromosome system X0 and chromosome number 2n = 23 (22A + X0). Testis cells were stained with lacto-acetic orcein and silver nitrate so that changes in the morphology ...