Cytogenetic studies inPodocnemis expansaandPodocnemis sextuberculata(Testudines, Podocnemididae), turtles of the Brazilian Amazon

Cleiton Fantin, Luiz Alberto dos Santos Monjeló
2011 Caryologia (Firenze)  
Cytogenetic studies were conducted with Podocnemis expansa and Podocnemis sextuberculata, turtles of the Brazilian Amazon, aimed at a better characterization of the chromosomes of these species. To obtain mitotic chromosomes, lymphocytes were grown in a culture medium for karyotypes (RPMI), and harvested cells were treated to obtain metaphase chromosomes. The results showed the karyotypic number for P. sextuberculata and P. expansa to be 2n = 28 chromosomes; in both species the karyotypes
more » ... ed 5 pairs of macrochromosomes and 9 pairs of microchromosomes, that is, 16m + 2sm + 10a and NF = 46. Visualization of the nucleolar organizing region (NOR) in these two species was obtained by silver nitrate staining, and provided evidence of a simple NOR in the pericentromeric region of the fi rst chromosomal pair. The diploid number was found to be the same as that described in the literature but NOR data are described for the fi rst time.
doi:10.1080/00087114.2002.10589777 fatcat:3a7o3m5uvnfqfoj5ajvwh35y2m