Biogeographic regions of Central Argentina based on snake distrib ution: evaluating two differe nt methodological approaches

NORI, JAVIER; DIAZ-GOMEZ, JUAN MANUEL; LEYNAUD, GERARDO

JOURNAL OF NATURAL HISTORY

TAYLOR & FRANCIS LTD

Lugar: Oxford; Año: 2011 vol. 45 p. 1005 - 1020

0022-2933

Regionalizat ion s tudies attempt to divide an area into regions by studying the d is-tribution of its biota. Here we used snake distribution in Central Argentina t orecogniz e d istribution p atterns, and t hen compared t wo methods (cluster analy-sis and endemism analysis) and the patterns found with previously defined regions.Both analyses recovered Chaco and, within Chaco, the s ubregion Chaco Serrano,as well as all t he snake s pecies that are t hreatened o r range-restricted o ccurringonly in t he Chaco region, wh ich h as been severely defo rested in the last d ecades.The Espinal region was not recovered by cluster analysis or NDM software, andmay b e considered an ?impoverished? Chaco or a t ransition zone. T he Pampaswas only recovered by cluster analysis. NDM appears t o b e more robust t han clus-ter analysis, wh ereas t he latter s eems to be very sensitive t o s ampling p ro blems,sometimes identifying spurious areas o r areas characteriz ed by h aving n o exclusivespecies.