Some sort of insect that seemed to like Herb Paris pollen or nectar?
No interactions present.
A.k.a. The Marsh Marigold Moth, is described as a pollen-feeder that is on the wing from May-June. Given that most Springtime events now occur around a fortnight earlier than "tradition" has it, this is a good bet.
First thought was that they were beetles, but didn't look quite right. Like the name - English and Latin versions both very descriptive, even though on the wrong plant!
Lat/Lng: 52.241781, -1.70818
OS grid ref: SP200604
Nature reserve (Warwickshire Wildlife Trust)