[Help-bash] group

[Val Krem]

Hi all,

In one folder a I have several files( >200). These files do have the same 
columns(variables).  The file names do have two patterns and want concatenate 
these files into two groups based on their file name pattern.

The file names look like as follow.
Region-19940726.csv
Region-19940816.csv
Region-19940920.csv
Region-19941018.csv
Region-19941122.csv
Region.csv
RegionAB-19940726.csv
RegionAB-19940816.csv
RegionAB-19940920.csv
RegionAB-19941018.csv
RegionAB-19941122.csv
RegionAB.csv

The first file (file1)  should include all files that starts with 'RegionAB' 
and inlcude the following files

RegionAB-19940726.csv
RegionAB-19940816.csv
RegionAB-19940920.csv
RegionAB-19941018.csv
RegionAB-19941122.csv
RegionAB.csv

The second output  file  (file2) should include all files that start with 
'Region'

Region-19940726.csv
Region-19940816.csv
Region-19940920.csv
Region-19941018.csv
Region-19941122.csv
Region.csv

Is there an efficient way of doing this?

thank you in advance