Thanks for your responses, Ive had a good look over the tree & couldn't find any other ones. Is it possible to just have one on the tree or is it a case of if there's one there's a problem ?
I'm happy to hit it with some confidor but I did just do a heap of pruning including branches, could the confidor do more harm than good considering the tree would be under some stress from the work that has been done ?
There is no point in wasting pesticide if there is nothing to kill.
It is certainly possible that there could be just one. You are now alert and can monitor a bit more closely to see if others turn up.
Part of the beauty of bonsai is that you can monitor the condition of an entire tree without trouble.
If you have one bug, pull it off, if you have two bugs, same. More bugs than you can count, start spraying.
After roughly 20 years of growing bonsai, I reckon I might just be starting to get the hang of it...