Chromosome Evolution in Lophyohylini (Amphibia, Anura, Hylinae)

SUÁREZ P; FERRO JM (PRIMERA AUTORIA CONJUNTA); NAGAMACHI, CY; CARDOZO DE; BLASCO-ZUÑIGA, A; SILVA, JB; MARCIANO-JR, E; COSTA, MA; ORRICO VGD; SOLÉ, M; ROBERTO, IJ; RIVERA, M; WILEY, JE; FAIVOVICH, J; BALDO, D; PIECZARKA, JC

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2020

1932-6203

The hyline tribe Lophyohylini includes 87 species oftreefrogs, of which cytogenetics aspects have been studied in less than 20% of them.In order to evaluate the evolution of some of its chromosome characters (NORposition, C-bands, and DAPI/CMA3 bands), we studied the karyotypes of 21 lophyohylines,16 of them for the first time, and analyzed them in a phylogenetic context.Most species showed similar karyotypes regarding chromosome number (2n = 24)and morphology (FN = 48), excepting Phyllodytesedelmoi and Osteocephalus buckleyi with 2n = 22 (FN = 44) and 2n =28 (FN = 50), respectively. The NOR location was variable among species andprovided valuable phylogenetic information. This marker was located in pair 11in all species of Trachycephalus, Itapotihyla langsdorffii, and Nyctimantisarapapa, representing the plesiomorphic condition of Lophyohylini. Besides,other apomorphic states were recovered for the clades comprising N. rugiceps and N. siemersi (NOR in pair 5), and Dryaderces pearsoni, Osteocephalus,and Osteopilus (NOR in pair 9). Phyllodytes presented variation for NORsposition; they were in pair 2 in P.edelmoi, pair 7 in P. melanomystax,and pair 8 in P. gyrinaethes and P. praeceptor. Polymorphisms in size,number, and activity of this marker were observed for N. siemersi, Osteocephalusfuscifacies, and some species of Trachycephalus.Remarkably, in N. siemersi NORs weredetected on a single chromosome in the two specimens studied by this technique,raising the question of how this complex polymorphism is maintained.Interstitial telomeric sequences were found in P. edelmoi, P. melanomystax,and Osteocephalus buckleyi, and theirpresence seems to be not related to the chromosome reorganization events.Finally, some species showed spontaneous rearrangements, possibly as a consequence of an uncommon phenomenon in anurancytogenetics: the presence of fragile sites or secondary constrictions notassociated with NORs. We propose that this rare feature would have played an important role in the evolution ofthis group of frogs. Fromthe evidence obtained in this and previous studies, we conclude thatLophyohylini presents a complex chromosome evolution.