A moth with a long proboscis

Down in the depths of the long grass and madly growing shrubs at the bottom of our garden, many insects are thriving. I walked down to the bottom through the tall cow parsley where I came across a collection of moths dancing around each other in the shadows of the trees. They all seemed to have very long proboscis and they seemed to be 'connecting' to each others in a kind of organised display.

I first saw this moth on a shrub nearby and then spotted several more resting on a different species close by. After a few minutes they would take off again and resume their dance. I tried to photograph them in mid-air, but of course it was nigh on impossible to focus handheld with a macro lens. I've added an extra to give a sense of what I saw.