I took this photo to let you all know this little bugger will eat the green above ground bits of your potatoes to smithereens. It is called the 26 or 28 spotted lady bug. I was going to waffle on about it but someone who I follow has already done a way better job than I might have.
So if you get yourself on over to Aussie Organic Gardening you can find out all about
Epilachna vigintioctopunctata and Epilachna vigintisexpunctata with some great links to other sites as well.