Post-extinction discovery of a population of the highly endemic colonial tuco-tuco (Ctenomys sociabilis)

TAMMONE, MAURO N.; LAVIN, BRIAN R.; PARDIÑAS, ULYSES F. J.; LACEY, EILEEN A.

JOURNAL OF MAMMALOGY

ALLIANCE COMMUNICATIONS GROUP DIVISION ALLEN PRESS

Lugar: Lawrence; Año: 2016 vol. 97 p. 1753 - 1763

0022-2372

Comparisons of a species? modern and historic geographic distributions can yield important insights into patternsof biodiversity, including faunal responses to environmental change. Using morphological and genetic analyses ofmuseum specimens and samples recently collected in the field, we document the historical occurrence of a populationof colonial tuco-tucos (Ctenomys sociabilis) from Laguna Nahuelquir in Chubut Province, Argentina. This localityrepresents a significant increase in the geographic distribution of this species, which had been thought to be endemicto the Sierra de Cuyín Manzano located ~130 km to the north in Neuquén Province. Field surveys of the LagunaNahuelquir locality failed to reveal extant populations of C. sociabilis; although the habitat at this location is generallyconsistent with areas occupied by C. sociabilis in the Cuyín Manzano, the Laguna Nahuelquir site is now occupiedby the Patagonian tuco-tuco, C. haigi. This apparent replacement of ctenomyid species is consistent with patternsof faunal turnover revealed by analyses of late Pleistocene?early Holocene cave deposits near the Sierra de CuyínManzano and supports the hypothesis that changes in local environmental conditions have contributed to the loss ofC. sociabilis from these localities. Thus, comparisons of historical and modern specimens of ctenomyids provideevidence of range retractions by colonial tuco-tucos over multiple time scales and add to a growing body of evidenceregarding the apparent effects of environmental change on the small mammal fauna of northern Patagonia.