Abstract

AbstractThe family Parodontidae is a small group of fish that has distinct morphological differences. Despite its conserved diploid number, structural cytogenetic polymorphisms involving sex chromosomes are commonly described in this group. Conversely, reports on numerical polymorphisms owing to the occurrence of supernumerary chromosomes are rare. To better understand the karyotype evolution of this group, we analyzed specimens of Parodon nasus collected in the Tres Bocas/PR stream, applying different cytogenetic techniques. All individuals presented 54 meta-submetacentric chromosomes, except for three females, which exhibited structural polymorphism. The NOR occurred on a pair of submetacentric chromosomes. Heterochromatin was distributed in some pericentromeric areas, predominating in the terminal regions. We detected B microchromosomes in four of the collected individuals, which were heterochromatic and bearers of 18S rDNA sites. This work deals with the first description of these chromosomes in the f...

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.