1. Chromosomal characterization of Amazonian freshwater stingrays with evidence for new karyomorphs and XX/XY sex chromosomes
- Author
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Jorge Ivan Rebelo Porto, Eliana Feldberg, and Francisco Carlos de Souza Valentim
- Subjects
Male ,0106 biological sciences ,0301 basic medicine ,Freshwater Stingray ,Subfamily ,Nucleolus ,Potamotrygon Motoro ,Elasmobranchs ,01 natural sciences ,cytogenetics ,Chromosome Analysis ,Heterochromatin ,Potamotrygon Leopoldi ,chromosomal rearrangements ,Potamotrygon ,Female ,Ploidy ,Potamotrygon Amazona ,Potamotrygon Constellata ,medicine.medical_specialty ,Karyotype Evolution ,lcsh:QH426-470 ,Biology ,03 medical and health sciences ,Genetics ,medicine ,Constitutive heterochromatin ,Potamotrygon Wallacei ,Controlled Study ,Chromosome Nor ,Molecular Biology ,karyotypic diversity ,Taxonomy ,Freshwater Species ,Plesiotrygon Iwamae ,sex chromosomes ,Potamotrygon Scobina ,Cytogenetics ,Karyotype 46,xx ,Chromosome ,Karyotype 46,xy ,Nonhuman ,biology.organism_classification ,lcsh:Genetics ,030104 developmental biology ,Evolutionary biology ,Karyotyping ,Plesiotrygon iwamae ,Animal Genetics ,Potamotrygon Orbignyi ,010606 plant biology & botany - Abstract
Cytogenetic studies in the subfamily Potamotrygoninae have provided valuable insights into the understanding of the evolution and diversification of its species. In the present study, the chromosomal features of seven nominal potamotrygonin species are provided: Plesiotrygon iwamae (2n=74, FN=120), Potamotrygon amazona (2n=66, FN=107), P. constellata (2n=66, FN=110), P. leopoldi (2n=64, FN=102), P. motoro (2n=66, FN=106) from four different localities, and P. orbignyi (2n=66, FN=106), P. scobina (2n=66, FN=104), from Central Amazon. Additionally, we found a new karyomorph in P. wallacei. We considered the localization of Nucleolus Organizer Regions (NORs), as well as the pattern of constitutive heterochromatin, as species-specific characters. We found an XX/XY sex chromosome system in P. orbignyi, and we suggest that P. scobina and P. amazona also possess the same sex chromosome system. Overall, the chromosomal evolution in this group appears to have progressed towards a reduction in diploid number, with a concomitant increase in the number of bi-armed and nucleolar chromosomes. © 2019, Brazilian Journal of Genetics. All rights reserved.
- Published
- 2019
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