title: Comparative cytogenetics of tree frogs of theDendropsophus marmoratus(Laurenti, 1768) group: conserved karyotypes and interstitial telomeric sequences.
abstract: The diploid number 2n = 30 is a presumed synapomorphy ofDendropsophusFitzinger, 1843, although a noticeable variation in the number of biarmed/telocentric chromosomes is observed in this genus. Such a variation suggests that several chromosomal rearrangements took place after the evolutionary origin of the hypothetical ancestral 30-chromosome karyotype; however, the inferred rearrangements remain unknown. Distinct numbers of telocentric chromosomes are found in the two most cytogenetically studied species groups ofDendropsophus. In contrast, all three species of theDendropsophus marmoratus(Laurenti, 1768) group that are already karyotyped presented five pairs of telocentric chromosomes. In this study, we analyzed cytogenetically three additional species of this group to investigate if the number of telocentric chromosomes in this group is not as variable as in otherDendropsophusgroups. We described the karyotypes ofDendropsophus seniculus(Cope, 1868),Dendropsophus soaresi(Caramaschi & Jim, 1983) andDendropsophus novaisi(Bokermann, 1968) based on Giemsa staining, C-banding, silver impregnation andin situhybridization with telomeric probes.Dendropsophus seniculus,Dendropsophus soaresiandDendropsophus novaisipresented five pairs of telocentric chromosomes, as did the remaining species of the group previously karyotyped. Though the species of this group show a high degree of karyotypic similarity,Dendropsophus soaresiwas unique in presenting large blocks of het-ITSs (heterochromatic internal telomeric sequences) in the majority of the centromeres. Although the ITSs have been interpreted as evidence of ancestral chromosomal fusions and inversions, the het-ITSs detected in the karyotype ofDendropsophus soaresicould not be explained as direct remnants of ancestral chromosomal rearrangements because no evidence of chromosomal changes emerged from the comparison of the karyotypes of all of the species of theDendropsophus marmoratusgroup.
authors.affiliation: Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, 13083-863 Campinas, São Paulo, Brasil.
authors.forename: Lívia S R
authors.initials: LS
authors.lastname: Teixeira
authors.affiliation: Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, 13083-863 Campinas, São Paulo, Brasil.
authors.forename: Karin Regina
authors.initials: KR
authors.lastname: Seger
authors.affiliation: Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, 13083-863 Campinas, São Paulo, Brasil.
authors.forename: Cíntia Pelegrineti
authors.initials: CP
authors.lastname: Targueta
authors.affiliation: Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, 45662-900 Ilhéus, Bahia, Brasil.
authors.forename: Victor G Dill
authors.initials: VG
authors.lastname: Orrico
authors.affiliation: Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, 13083-863 Campinas, São Paulo, Brasil.
authors.forename: Luciana Bolsoni
authors.initials: LB
authors.lastname: Lourenço
keywords: Anura; Chromosomes; telomeric sequence