Well spotted Bert!
With a quick search it seems to be PPMX 071735.3-122736 in the the PPMX Catalog (Position and Proper Motions Extended), with a proper motion in RA of 55.25mas/yr and in DEC of
-324.17mas/yr (info from VizieR).
http://vizier.u-strasbg.fr/viz-bin/V...71735.3-122736
The movement shown in your image is a small fraction of an arcminute but the DSS Colored plates would still have to be reasonably old - can't find a date for them.
Cheers -