Penny spotted something hairy creeping past the back door. I managed to capture it in a small plastic petri dish.
Unfortunately it then refused to do anything but curl up.
LCD microscope photo:
I let it go again and waited for it to start moving. Unfortunately for a small beast it can really move fast. The best I could get as it rushed for cover:
It turned out to be a Ruby Tiger Moth caterpillar. Hair in tufts, about 25mm long. Right time of year for a second brood. Have seen the adult moths from time to time in the longer parts of the lawn.