Occurrence of sexual chromosome, of the type ZZ/ZW, in Ancistrus cf. dubius (Loricariidae, Ancistrinae) of the Paraguay River Basin, Mato Grosso, Brazil

  title={Occurrence of sexual chromosome, of the type ZZ/ZW, in Ancistrus cf. dubius (Loricariidae, Ancistrinae) of the Paraguay River Basin, Mato Grosso, Brazil},
  author={M. Sandra and Roberto Ferreira Artoni and Carlos Suetoshi Miyazawa},
  pages={327 - 331}
Abstract Fifteen specimens of Ancistrus cf. dubius of the Paraguay River Basin (Serra das Araras /Barra dos Bugres, Mato Grosso state, Brazil) were studied cytogenetically with characterization and of constitutive heterochromatin and nucleolar organizer regions (NORs) evidenced by C-bands, flurochrome GC-rich DA/CMA3 and silverstaining. For the first time, chromosomic heteromosphism related to sex, of the type ZZ/ZW, was observed in Ancistrinae fish. Thus, in the karyotype of males a pair of Z… 

Chromosomic characterization of four populations and occurence of sexual chromosomes of type XX / XY , in the pantanal basin of Mato Grosso , Brazil

Four populations of Ancistrus cf. dubius (Loricariidae, Ancistrinae) were analyzed cytogenetically. They were from different rivers and creeks of the Pantanal Basin, in the state of Mato Grosso,

Ancistrus cf. dubius (Siluriformes, Ancistrinae), a complex of species. 1. Chromosomic characterization of four populations and occurence of sexual chromosomes of type XX/XY, in the pantanal basin of Mato Grosso, Brazil

Abstract Four populations of Ancistrus cf. dubius (Loricariidae, Ancistrinae) were analyzed cytogenetically. They were from different rivers and creeks of the Pantanal Basin, in the state of Mato

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Karyotype description of three species of Loricariidae (Siluriformes) and occurrence of the ZZ/ZW sexual system in Hemiancistrus spilomma Cardoso & Lucinda, 2003

The data showed in this work reveal particular chromosomal characteristics, important for a good recognition of both Hemincistrus species, and show the importance of the insertion of cytogenetic data on taxonomic phylogenetic studies.

Chromosome polymorphism in Ancistrus cuiabae Knaack, 1999 (Siluriformes: Loricariidae: Ancistrini)

The chromosomal polymorphism of C-positive heterochromati cbands were adjacent to the rDNA sites in the corresponding chromosomes.

First description of the karyotype and Ag-NORs localization of Brachychalcinus retrospina (Pisces: Characidae: Stethaprioninae) from Upper Paraguay Basin, Mato Grosso State, Brazil

The results for B. retrospina corroborate those found for other species this subfamily, both in chromosome number and markings of Ag-NORs, indicating some stability chromosomal for this group.

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Karyotype, sex chromosome system and cytogenetics characteristics of an unidentified species of the genus Apareiodon originating from Piquiri River were investigated using differential staining techniques and fluorescent in situ hybridization with 5S and 18S rDNA probes.



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C-banding analysis of the mitotic chromosomes revealed constitutive heterochromatin in the centromeric regions of all acrocentrics, however, small metacentrics were C-band negative.

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A Heteromorphic ZZ/ZW Sex Chromosome System in Fish, Genus Hypostomus (Loricariidae)

The available data indicate that the differentiation of this sex chromosome system may have occurred by a pericentric inversion, followed by length reduction in an ancestral chromosome similar to the Z one, originating a W chromosome like that now observed in the female karyotype of this fish species.

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