Morphometric and allozymic characterization of populations of Necromys benefactus populations in central Argentina.

PROVENSAL, M.C., CALDERÓN, G.E, CHIAPPERO, M.B., GARDENAL, C.N., POLOP, J.J. Y SABATTINI, M.S.

MASTOZOOLOGíA NEOTROPICAL

SAREM

Lugar: Mendoza; Año: 2005 vol. 12 p. 261 - 268

0327-9383

The precise determination of species boundaries and relationships among taxa in Sigmodontinae rodents is particularly difficult in some groups, mainly because of the poor morphological differentiations accompanying the speciation process in several genera. In this paper, we compare individuals assigned to the genus Necromys trapped in different localities of the Pampean region of Argentina, using morphometric variables and allozymic frequencies. The comparative analysis of external characters and qualitative parameters of the skull in individuals from two localities of the Pampean region, allows to assign them to the species Necromys benefactus. Morphometric parameters between individuals captured in the field and their descendants from laboratory colonies did not show significant differentiation. No fixed exclusive alleles for any of the populations were detected and Nei’s genetic distance value among populations were very low (between 0.007 and 0.02), confirming that the rodents sampled belong to a single species.