The 14-spot Ladybird is rather small - about the size of a match head.
Some flies just attract attention, and the very spiny appearance of this one makes it a Tachinid Fly. These are parasites that attack caterpillars in a similar manner to Ichneumonids, but instead of laying their eggs inside the caterpillar, they lay their eggs on the outside and their larvae enter and consume the caterpillar before pupating inside the empty skin.
Captive studies indicate that around 80% of moth and butterfly caterpillars are parasitised. I can certainly believe the figure is high, since I see a great many Tachinids and Ichneumonids every day.
For those of you able to watch RTE television, this website will be featured on RTE1 on Tuesday 26th May in the program 'Living the Wildlife'.