CYTOGENETICS OF FIVE SPECIES OF PHYSALAEMUS CUVIERI GROUP (ANURA, LEIUPERIDAE) WITH EMPHASIS ON NOR VARIABILITY.

QUINDERÉ, YEDA; LOURENÇO LUCIANA; ANDRADE, G.; TOMATIS, CRISTIAN; BALDO, DIEGO; LIMA, J.; VITTORAZZI, S; RECCO-PIMENTEL SIRLHEY

Congreso; 16th International Chromosome Conference.; 2007

The Physalaemus cuvieri group comprises nine species of the genus. Its phylogenetic relationships are unclear and little is known about their karyotypes. We investigated six populations of P. cuvieri from Brazil and three from Argentina, and described the karyotypes of P. albonotatus, P. centralis, P. cuqui and P. ephippifer. Metaphases were stained with Giemsa and submitted to C-band (except for P. cuqui), silver staining and FISH with rDNA probes. All species had 2n = 22 and NF = 44, and similar karyotypes concerning the morphology of the chromosomes, specially the seven first pairs. The NORs occurred mainly in the smaller chromosomal pairs, except for P. cuvieri from Porto Nacional, in which chromosome pairs 1, 3 and 4 carried NORs, besides pair 10. C-band distribution was able to distinguish the specimens of Porto Nacional from all the other populations of P. cuvieri. All other Brazilian populations analyzed here had an NOR in chromosomal pair 8, whereas the Argentinian populations showed the principal NOR in pair 11. Specimens from only three populations of P. cuvieri from Brazil had also an NOR in chromosome 9. Interindividual variations in the number of NORs were observed in the populations of P. cuvieri, except for Palmeiras and Uberla?ndia. An intraindividual variation in NOR size was also detected in specimens from Uberla?ndia. A C-band was detected in the chromosome 5 in all P. cuvieri and also in P. albonotatus, P. centralis and P. ephippifer. The NOR pattern was very important to differ the species each other. In P. ephippifer an interesting heteromorphism in NOR and heterochromatin occurrence between the homologues of pair 8 was exclusively found in females, suggesting the presence of sex chromosomes.