title: A comparative study of two marine catfish (Siluriformes, Ariidae): Cytogenetic tools for determining cytotaxonomy and karyotype evolution.
abstract: The family Ariidae comprises approximately 130 catfish species on both warm-temperate and tropical continental shelves around the world. The systematics of the group is problematic, with several misidentification problems. In order to better understand the evolutionary relationships in the family, the present study used a cytogenetic approach to characterize two populations of Genidens genidens and two populations of Aspistor luniscutis from the southern coast of Brazil using conventional techniques and fluorescent in situ hybridization with 18S rDNA probes. The two species had the same diploid number (2n = 56), high fundamental numbers and similar banding patterns, thereby corroborating the karyotypic homogeneity proposed for the group. Single nucleolus organizer regions (NORs) were found in the genus Genidens and multiple NORs were found in Aspistor, which are considered an important cytotaxonomic marker for this genus. Karyotypic evolution trends were hypothesized, providing a better understanding of the karyotype diversity and chromosome evolution processes.
authors.affiliation: Universidade Federal do Paraná, Programa de Pós-Graduação em Genética, Centro Politécnico, Jardim das Américas, 81531-990 Curitiba - PR, Brazil.
authors.forename: Thaís Saad
authors.initials: TS
authors.lastname: Sczepanski
authors.forename: Rafael Bueno
authors.initials: RB
authors.lastname: Noleto
authors.forename: Marta Margarete
authors.initials: MM
authors.lastname: Cestari
authors.forename: Roberto Ferreira
authors.initials: RF
authors.lastname: Artoni
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001938:Brazil; D002397:Catfishes / Q000145:classification* / Q000235:genetics*; D002871:Chromosome Banding; D003582:Cytogenetics / Q000379:methods*; D004171:Diploidy; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping / Q000379:methods; D009697:Nucleolus Organizer Region; D012337:RNA, Ribosomal, 18S / Q000235:genetics
chemical_list: D012337:RNA, Ribosomal, 18S