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The studied area is located in Southern South America and correspond to 
the Patagonian and Subantartic subregions (Morrone, 2001). The 
definition of this region has been based mainly on its floristic 
composition and only a few studies were based on mammal or insect 
distributions. The present study is to our knowledge, the largest of 
this kind for the area. Originally the matrix was conformed by 19845 
data entries of 1041 species. This matrix was filtered by eliminating 
the species with only one registry or species with more than one 
registry but from the same locality. The final matrix was conformed by 
999 species of insects based on more than 12000 georeferenced data 
entries of insects of the orders Coleoptera and Hymenoptera. This 
information was gathered from systematic revisions and from the 
collections of the main museums and institutions of Argentina, Chile and 
Brazil. The program NDM version 2.2 was used to analyze the matrix by 
using different grid sizes and fill scores. Five analyses were made: 1) 
1o X 1o grid without fill, 2) 1o X 1o grid with fill of 30, 3) 0.5o X 
0.5o grid, 4) 1o X 0.5o (West – East oriented grid) and 5) 0.5o X 1o 
(North south oriented grid). Nested areas, conflictive areas and 
disjunctive areas were identified. Results of the search 1o X 1o grid 
with fill of 30 with posterior strict consensus of 40% was selected for 
a more detailed analysis. This search was selected because it recognizes 
the major number of not superimposed areas, 17 in total. The same search 
but without fill recognize six more areas not found in the first 
analysis. The other searches did not recognize new areas. Finally, four 
of the seven areas recognized by Dominguez et al., (2006) for the 
Patagonian steppe were recovered here. Furthermore, six areas matching 
with only one ecoregion (Valdivian forest, Chilean matorral, Magallanic 
sub-antartic forest, Patagonian steppe), several areas with associations 
of two or more ecoregions that were also proposed in previous studies 
(eg: Patagonian steppe - Low Monte), and two major areas that cover most 
of Chile and part of western Argentina were recovered. The use of a 
large data base allowed us the identification of a larger number of 
endemic areas with higher endemicity scores (defined by a higher number 
of species). The use of different grid sizes allowed the different areas 
raising the sensitivity of the analysis (e.g. the use of 1x0.5 grid 
allowed the differentiation of areas within the Maule region of Chile). 
Nevertheless, there are still many downfalls in the determination of 
areas of endemism: the lack of information for large areas such as the 
eastern region of the Argentine Patagonia. This problem does not arise 
in Chile, that is mostly well know.