What is eating my potato flowers?

Anyone have any ideas? I have never ever seen potato flowers disappear like this before?

What a challenging year this is proving to be on the allotment! The rain continues - unrelenting. In the past week we have had thunder and lightning, hail stones and rain the like of which I have never seen before.
And the plants struggle with so much wet and the attacks from slugs and snails which are delighting in the conditions.
Some things have been good - strawberries were amazing albeit two weeks late in coming - but they are now over. The new potatoes are tasty and abundant and the perpetual spinach and swiss chard are keeping me in healthy greens!
The broad beans need another week probably to swell up but the crop doesn't look too bad, as long as the pigeons stay away. And the various brassicas, totally protected by netting from the unwelcome attention of birds and butterflies, are growing well.

As soon as the ground dries a little (if it ever does?) I shall tidy up the strawberry bed, digging out the oldest row and planting a new row from healthy looking runners, on a three year rotation plan. Then I shall put plenty of manure down between the rows, to feed them and also to keep weeds at bay  - then I can forget about them for another year.
I also intend this year to sow some broad beans where the potatoes are being cleared, hoping for an early spring harvest next year. I've never done this before but others do with seemingly good results. And I shall sow some more spinach and swiss chard to keep the supply to the kitchen going.
My main hope now is for a late summer burst of warmth and sunshine to give the poor courgettes, pumpkins, squash, etc a chance to grow and mature - otherwise I shall be missing out on beautiful squashes to store over winter for lovely roast vegetables.