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Non-homologous sex chromosomes in two species of the genus Eigenmannia (Teleostei : Gymnotiformes)
(KARGER, 2008)
The Neotropical genus Eigenmannia is a fish group with unknown species diversity where representatives possess a broad range of chromosomal sex determining systems namely XY/XX, X1X2Y/X1X1X2X2, ZZ/ZW as well as homomorphic ...
Spontaneous triploidy and NOR activity in Eigenmannia sp. (Pisces, Sternopygidae) from the Amazon basin
(1985-05-01)
The occurrence of a natural triploid among diploid individuals of Eigenmannia sp from the Amazon basin is described. The diploid individuals had 2n=31 and 32 chromosomes, the difference in chromosome number being due to a ...
Chromosome evolution in fish: sex chromosome variability in Eigenmannia virescens (Gymnotiformes : Sternopygidae)
(Karger, 2002-01-01)
New data are presented on the sex chromosomes of the fish species Eigenmannia virescens (Gymnotiformes, Sternopygidae). A new finding, involving the occurrence of ZZ/ ZW sex chromosomes, is described in specimens sampled ...
Sex chromosome evolution in fish: the formation of the neo-Y chromosome in Eigenmannia (Gymnotiformes)
(Springer, 2000-01-01)
Chromosomes of a species of Eigenmannia presenting a X1X1X2X2:X1X2Y sex chromosome system, resulting from a Y-autosome Robertsonian translocation, were analyzed using the C-banding technique, chromomycin A(3) (CMA(3)) and ...
Chromosome evolution in fish: sex chromosome variability in Eigenmannia virescens (Gymnotiformes : Sternopygidae)
(Karger, 2002-01-01)
New data are presented on the sex chromosomes of the fish species Eigenmannia virescens (Gymnotiformes, Sternopygidae). A new finding, involving the occurrence of ZZ/ ZW sex chromosomes, is described in specimens sampled ...
Spontaneous triploidy and NOR activity in Eigenmannia sp. (Pisces, Sternopygidae) from the Amazon basin
(1985-05-01)
The occurrence of a natural triploid among diploid individuals of Eigenmannia sp from the Amazon basin is described. The diploid individuals had 2n=31 and 32 chromosomes, the difference in chromosome number being due to a ...
XX : XY sex chromosome system with X heterochromatinization: an early stage of sex chromosome differentiation in the Neotropic electric eel Eigenmannia virescens
(Karger, 2001-01-01)
An early stage of sex chromosome differentiation is reported to occur in the electric eel Eigenmannia virescens (Pisces, Sternopygidae) from populations of two tributaries of the Parana river system (Brazil). Cytogenetic ...
Sex chromosome evolution in fish: the formation of the neo-Y chromosome in Eigenmannia (Gymnotiformes)
(Springer, 2000-01-01)
Chromosomes of a species of Eigenmannia presenting a X1X1X2X2:X1X2Y sex chromosome system, resulting from a Y-autosome Robertsonian translocation, were analyzed using the C-banding technique, chromomycin A(3) (CMA(3)) and ...