Karyotypic diversity in seven Amazonian anurans in the genus Hypsiboas (family Hylidae).
BACKGROUND
Hypsiboas species have been divided into seven groups using morphological and genetic characters, but for most of the species, there is no cytogenetic information available. A cytogenetic analysis using conventional staining, C-banding, silver staining, and fluorescence in situ hybridization (FISH) with telomeric sequence probes were used to investigate the karyotype of seven Amazon species of the genus Hypsiboas belonging to the following intrageneric groups: H. punctatus (H. cinerascens), H. semilineatus (H. boans, H. geographicus, and H. wavrini), and H. albopunctatus (H. lanciformis, H. multifasciatus, and H. raniceps). The aim was to differentiate between the karyotypes and use the chromosomal markers to distinguish between the Hypsiboas groups. The data were compared with a previous phylogenetic proposal for these anurans. In addition, H. lanciformis, H. boans, and H. wavrini are described here for the first time, and we characterize the diploid numbers for H. cinerascens, H. geographicus, H. multifasciatus, and H. raniceps.


RESULTS
The diploid number for all of the species analyzed was 24, with the exception of Hypsiboas lanciformis, which had 2n = 22 chromosomes. The constitutive heterochromatin distribution, nucleolar organizer region locations, and interstitial telomeric sites differed between the species. A hypothesis that the heterochromatic patterns are evolving is proposed, with the divergence of the groups probably involving events such as an increase in the heterochromatin in the species of the H. semilineatus group. The FISH conducted with the telomeric probes detected sites in the terminal regions of all of the chromosomes of all species. Interstitial telomeric sites were detected in three species belonging to the H. semilineatus group: H. boans, H. geographicus, and H. wavrini.


CONCLUSIONS
The results of this study reinforce the complexity previously observed within the genus Hypsiboas and in the different groups that compose this taxon. More studies are needed focusing on this group and covering larger sampling areas, especially in the Brazilian Amazon, to improve our understanding of this fascinating and complex group.
Instituto Nacional de Pesquisas da Amazônia, Programa de Pós-Graduação em Genética, Conservação e Biologia Evolutiva, Av, André Araújo, 2936, 69080-971 Manaus, AM, Brazil. tldmattos@gmail.com.
Thais Lemos
TL
de Mattos
Ana Carolina
AC
Coelho
Carlos Henrique
CH
Schneider
David Otávio Carmo
DO
Telles
Marcelo
M
Menin
Maria Claudia
MC
Gross
D000818:Animals; D001001:Anura / Q000145:classification / Q000235:genetics*; D001938:Brazil; D004171:Diploidy; D005260:Female; D006570:Heterochromatin / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D059785:Karyotype; D008297:Male; D009697:Nucleolus Organizer Region / Q000235:genetics; D010802:Phylogeny; D013045:Species Specificity; D016615:Telomere / Q000235:genetics
D006570:Heterochromatin