Chromosome evolution in Cophomantini (Amphibia, Anura, Hylinae)

FERRO, JUAN M.; CARDOZO, DARIO E.; SUÁREZ, PABLO; BOERIS, JUAN M.; BLASCO-ZÚÑIGA, AILIN; BARBERO, GASTÓN; GOMES, ANDERSON; GAZONI, THIAGO; COSTA, WILLIAM; NAGAMACHI, CLEUSA Y.; RIVERA, MIRYAN; PARISE-MALTEMPI, PATRICIA P.; WILEY, JOHN E.; PIECZARKA, JULIO C.; HADDAD, CELIO F. B.; FAIVOVICH, JULIÁN; BALDO, DIEGO

PLOS ONE

PUBLIC LIBRARY SCIENCE

Año: 2018 vol. 13

1932-6203

The hylid tribe Cophomantini is a diverse clade of Neotropical treefrogs composed of thegenera Aplastodiscus, Boana, Bokermannohyla, Hyloscirtus, and Myersiohyla. The phylogeneticrelationships of Cophomantini have been comprehensively reviewed in the literature,providing a suitable framework for the study of chromosome evolution. Employingdifferent banding techniques, we studied the chromosomes of 25 species of Boana and 3 ofHyloscirtus; thus providing, for the first time, data for Hyloscirtus and for 15 species ofBoana. Most species showed karyotypes with 2n = 2x = 24 chromosomes; some species ofthe B. albopunctata group have 2n = 2x = 22, and H. alytolylax has 2n = 2x = 20. Karyotypesare all bi-armed in most species presented, with the exception of H. larinopygion (FN = 46)and H. alytolylax (FN = 38), with karyotypes that have a single pair of small telocentric chromosomes.In most species of Boana, NORs are observed in a single pair of chromosomes,mostly in the small chromosomes, although in some species of the B. albopunctata, B. pulchella,and B. semilineata groups, this marker occurs on the larger pairs 8, 1, and 7, respectively.In Hyloscirtus, NOR position differs in the three studied species: H. alytolylax (4p), H.palmeri (4q), and H. larinopygion (1p). Heterochromatin is a variable marker that couldprovide valuable evidence, but it would be necesserary to understand the molecular compositionof the C-bands that are observed in different species in order to test its putative homology. In H. alytolylax, a centromeric DAPI+ band was observed on one homologue ofchromosome pair 2. The band was present in males but absent in females, providing evidencefor an XX/XY sex determining system in this species. We review and discuss theimportance of the different chromosome markers (NOR position, C-bands, and DAPI/CMA3patterns) for their impact on the taxonomy and karyotype evolution in Cophomantini.