Sex chromosomes have evolved repeatedly across eukaryotes. The emergence of a sex‐determining (SD) locus is expected to progressively restrict recombination, driving convergent molecular differentiation. However, evidence from taxa like teleost fishes, representing over half of vertebrate species with unmatched diversity in SD systems, challenges this model. Teleost sex chromosomes are often difficult to detect as they experie...

Using African annual killifishes of the genus Nothobranchius from temporary savannah pools with rapid karyotype and sex chromosome evolution, we analysed the chromosomal distribution of telomeric (TTAGGG) n repeat and Nfu‐SatC satellite DNA (satDNA; isolated from Nothobranchius furzeri ) in 15 species across the Nothobranchius killifish phylogeny, and with Fundulosoma thierryi as an out‐group. Our fluorescence in situ hybridiz...

Satellite DNA (satDNA) is a rapidly evolving class of tandem repeats, with some monomers being involved in centromere organization and function. To identify repeats associated with (peri)centromeric regions, we investigated satDNA across Southern and Coastal clades of African annual killifishes of the genus Nothobranchius . Molecular cytogenetic and bioinformatic analyses revealed that two previously identified satellites, des...

Rineloricaria is the most diverse genus within the freshwater fish subfamily Loricariinae, and it is widely distributed in the Neotropical region. Despite limited cytogenetic data, records from southern and south‐eastern Brazil suggest a high rate of chromosomal rearrangements in this genus, mirrored in remarkable inter‐ and intraspecific karyotype variability. In the present work, we investigated the karyotype features of Rin...