First report of B chromosomes in three neotropical thorny catfishes (Siluriformes, Doradidae)

• Autores: Takagui, Fábio Hiroshi; Dias, Ana Lucia; Olivan Birindelli, José Luís; Swarça, Ana Claudia; Da Rosa, Renata; Lui, Roberto Laridondo; Fenocchio, Alberto Sergio; Giuliano-Caetano, Lucia
• Año de publicación: 2017
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Centric fusión; Chromosomal rearrangements; Diploid number; Neotropical fish; Pericentric inversions; Supernumerary chromosome
• Institución: Universidad Nacional de Misiones

Fil: Takagui, Fábio Hiroshi. Universidad Estatal de Londrina. Centro de Ciencias Biológicas. Departamento de Biología General. Laboratorio de Citogenética Animal; Brasil.
Fil: Dias, Ana Lucia. Universidad Estatal de Londrina. Centro de Ciencias Biológicas. Departamento de Biología General. Laboratorio de Citogenética Animal; Brasil.
Fil: Olivan Birindelli, José Luís. Universidad Estatal de Londrina. Centro de Ciencias Biológicas. Departamento de Biología animal y vegetal. Museo de Zoología; Brasil.
Fil: Swarça, Ana Claudia. Universidad Estatal de Londrina. Centro de Ciencias Biológicas. Departamento de Histología. Laboratorio de Histología y Genética; Brasil.
Fil: Da Rosa, Renata. Universidad Estatal de Londrina. Centro de Ciencias Biológicas. Departamento de Biología General. Laboratorio de Citogenética Animal; Brasil.
Fil: Lui, Roberto Laridondo. Universidad del Oeste de Paraná. Centro de Ciencias Biológicas y de la Salud. Laboratorio de Citogenética; Brasil.
Fil: Fenocchio, Alberto Sergio. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Departamento de Genética. Laboratorio de Citogenética General; Argentina.
Fil: Giuliano-Caetano, Lucia. Universidad Estatal de Londrina. Centro de Ciencias Biológicas. Departamento de Biología General. Laboratorio de Citogenética Animal; Brasil.
The family Doradidae (Siluriformes) is an important group of fishes endemic to freshwater ecosystems in South America. Some cytogenetic studies have been conducted focused on the group; however, there are no reports on the occurrence of B chromosomes for the family. In this paper the chromosomal characteristics of Platydoras armatulus (Valenciennes, 1840), Pterodoras granulosus (Valenciennes, 1821) and Ossancora punctata (Kner, 1855) were investigated through classical cytogenetics approaches. The conventional staining reveals 2n=58 in Platydoras armatulus and Pterodoras granulosus, however with distinct karyotypic formulae, possibly originated by pericentric inversions. In Ossancora punctata a derivate karyotype was described with 2n=66 and predominance of acrocentric chromosomes. The C banding pattern was resolutive in discriminating the three species, being considered an important cytotaxonomic marker. All species showed B chromosomes totally heterochromatic with non-Mendelian segregation during meiosis and low frequencies in mitotic cells. The probably origin of these additional elements was through fragmentations of chromosomes of the standard complement, which occurred recently and independently in these three species. The diploid number observed in O. punctata is an evidence of centric fusions and up to the moment it is the highest diploid number reported for Doradidae.