Diversity of tuco-tucos (Ctenomys, Rodentia) in the Northeastern wetlands from Argentina: mitochondrial phylogeny and chromosomal evolution.

CARABALLO, DIEGO ALFREDO; ABRUZZESE, GISELLE ADRIANA; ROSSI, MARIA SUSANA

GENETICA

SPRINGER

Lugar: Berlin; Año: 2012 vol. 140 p. 125 - 136

0016-6707

Tuco-tucos (small subterranean rodents of the genusCtenomys) that inhabit sandy soils of the area under the influence of the second largest wetland of South America, in Northeastern Argentina (Corrientes province), are a complex of species and forms whose taxonomic status were not defined, nor are the evolutionary relationships among them. The tuco-tuco populations of this area exhibit one of the most ample grades of chromosomal variability within the genus. In order to analyze evolutionary rela-tionships within the Corrientes group and its chromosomal variability, we completed the missing karyotypic infor-mation and performed a phylogenetic analysis. We obtained partial sequences of three mitochondrial markers: D-loop, cytochrome b and cytochrome oxidase I. The Corrientes group was monophyletic and split into three main clades that grouped related karyomorphs. The phy-logeny suggested an ancestral condition of the karyomorph with diploid number (2n) 70 and fundamental number (FN) 84 that has evolved mainly via reductions of the FN although amplifications occurred in certain lineages. We discuss the relationship between patterns of chromosomal variability and species and groups boundaries. From the three main clades the one named ibera´ exhibited a remarkable karyotypic homogeneity, and could be con-sidered as an independent and cohesive evolutionary line-age. On the contrary, the former recognized species C. dorbignyiis a polyphyletic lineage and hence its sys-tematic classification should be reviewe.