Consulta: creatorFacets:"Gross,Maria Claudia"
Registros recuperados: 5
Data/hora: 09/06/2024 18:03:34

Population structure, fluctuating asymmetry and genetic variability in an endemic and highly isolated Astyanax fish population (Characidae)
Provedor de dados: 74
Autores: Gross,Maria Claudia; Schneider,Carlos Henrique; Matiello,Mara Cristina de Almeida; Leite,Maysa de Lima; Bertollo,Luiz Antonio Carlos; Artoni,Roberto Ferreira.
Morphological and chromosomal markers were used to infer the structure and genetic variability of a population of fish of the genus Astyanax, geographically isolated at sinkhole 2 of Vila Velha State Park, Paraná, Brazil. Two morphotypes types were observed, the standard phenotype I and phenotype II which showed an anatomical alteration probably due to an inbreeding process. Fluctuating asymmetry (FA) analysis of different characters showed low levels of morphological variation among the population from sinkhole 2 and in another population from the Tibagi river (Paraná, Brazil). The Astyanax karyotype was characterized in terms of chromosomal morphology, constitutive heterochromatin and nucleolar organizer regions. Males and females presented similar...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish; Astyanax sp.; Fluctuating asymmetry; Karyotype structure; Triploidy; Genetic conservation.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000400011

Comparative cytogenetics of Carnegiella marthae and Carnegiella strigata (Characiformes, Gasteropelecidae) and description of a ZZ/ZW sex chromosome system
Provedor de dados: 74
Autores: Terencio,Maria Leandra; Schneider,Carlos Henrique; Gross,Maria Claudia; Silva,Adailton Moreira da; Feldberg,Eliana; Porto,Jorge Ivan Rebelo.
Comparative cytogenetic analyses of hatchetfishes Carnegiella marthae and Carnegiella strigata (Gasteropelecidae) from the Rio Negro basin were performed using conventional Giemsa staining, silver (Ag) -staining and C-banding. The diploid chromosome numbers of both species equaled 2n = 50 but their karyotypes were distinct. We found evidence for sex chromosomes in C. marthae since karyotype of males presented 20 M + 12 SM + 4 ST + 14 A and ZZ ST chromosomes while the females presented 20 M + 12 SM + 4 ST + 14 A and ZW ST chromosomes of distinct size. Conversely, C. strigata presented 4 M + 4 SM + 2 ST + 40 A chromosomes without sex chromosome heteromorphism. Karyotypes of both species had two NOR-bearing SM chromosomes of distinct size indicating the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish cytogenetics; Karyotype differentiation; NOR phenotypes; Heteromorphic sex chromosome system; Cytotaxonomy.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200011

Cytotaxonomy and karyoevolution of the genus Crenicichla (Perciformes, Cichlidae)
Provedor de dados: 74
Autores: Benzaquem,Denise Corrêa; Feldberg,Eliana; Porto,Jorge Ivan Rebelo; Gross,Maria Claudia; Zuanon,Jansen Alfredo Sampaio.
Karyotypes of six cichlid species of the genus Crenicichla were investigated. The species C. cincta, C. inpa, C. reticulata, C. lugubris, and C. cf. johanna were collected from Amazon basin, and C. britskii was collected from the Paraná-Paraguai basin. All of the analysed species showed 2n = 48 chromosomes; however, C. cincta, C. lugubris, C. cf. johanna, and C. britskii had a karyotype formula of 8M-SM+40ST-A, FN = 56, while C. inpa and C. reticulata exhibited the formula 6M-SM+42ST-A, FN = 54. Analysis of active Ag-NORs revealed two NOR-bearing chromosomes in all species; however, theses cistrons were located on different chromosome pairs and/or in different chromosome locations in each species. This condition bears evolutionary significance, since it is...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Karyotype; Pike cichlid; Chromosome marker; Amazon.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200016

Astyanax aff. fasciatus Cuvier, 1819 (Teleostei; Characidae): evidences of a species complex in the upper rio Tibagi basin (Paraná, Brazil)
Provedor de dados: 83
Autores: Artoni,Roberto Ferreira; Shibatta,Oscar Akio; Gross,Maria Claudia; Schneider,Carlos Henrique; Almeida,Mara Cristina de; Vicari,Marcelo Ricardo; Bertollo,Luiz Antonio Carlos.
Four populations of Astyanax aff. fasciatus of the upper rio Tibagi (municipal district of Ponta Grossa, Paraná State, Brazil), had their karyotypes and morphometry analyzed. The cytogenetic data show the occurrence of distinct karyotypes (cytotypes), here named cytotype A, with 2n=48 chromosomes (6m+18sm+14st+10a), cytotype B, with 2n=50 chromosomes (8m+18sm+14st+10a) and cytotype C, with 2n=50 chromosomes (8m+18sm+14st+10a). The distribution pattern of the constitutive heterochromatin was very similar between cytotypes A and B, but diverged in relation to cytotype C. Distinct cytotypes may occur in sympatry in the upper rio Tibagi region, with the exception of the Furna 2 sample, which presents cytotype A exclusively. In addition, a specimen with 2n=49...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Tetra; Morphometrics; Karyotype; Sympatry; Cryptic species.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000200005

Cytogenetic analysis of the Amazon stingless bee Melipona seminigra merrillae reveals different chromosome number for the genus
Provedor de dados: 63
Autores: Francini,Izaura Bezerra; Gross,Maria Claudia; Nunes-Silva,Carlos Gustavo; Carvalho-Zilse,Gislene Almeida.
Cytogenetic analysis of the Amazon stingless bee Melipona seminigra merrillae, by conventional Giemsa staining and C-banding, revealed a different chromosome number for Melipona: 2n = 22 for females and diploid drones while the haploid drones present n = 11. There is no evidence of B chromosomes. This result contrasts with previous studies, in which the chromosome number of 19 Melipona species was determined as 2n = 18 for females and n = 9 for haploid males. Based on cytogenetic information available for other Melipona species, we propose that M. s. merrillae has a more derived diploid number. This indicates that chromosome number is not a conservative characteristic within the genus as previously thought. Cytogenetic data for stingless bees are scarce,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Meliponini; Neotropics; Cytogenetics; Diploid male chromosomes.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162011000500012