Abstract
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 Robertsonian rearrangement. The triploid individual presented 2n=46 and had two fused acrocentrics. NOR activity was present in the three homologues of triploid and a NOR polymorphism was detected in the triploid and diploids.
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De Almeida Toledo, L.F., Foresti, F. & De Almeida Toledo Filho, S. Spontaneous triploidy and NOR activity in Eigenmannia sp. (Pisces, Sternopygidae) from the Amazon basin. Genetica 66, 85–88 (1985). https://doi.org/10.1007/BF00139713
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DOI: https://doi.org/10.1007/BF00139713