Not the chelonian type, but Cassida rubiginosa, the thistle tortosie beetle. Not surprisingly sitting on thistle. Thsi pair were making the most of the warmest day here in Nottinghamshire so far this year. C. rubiginosa is probably the commonest of the tortosie beetles I encounter here in Notts, other include C. viridis, quite a big beetle compared to rubiginosa and C. vibex. If you search thistle, you'll find them.
Cassida rubiginosa,, male hopping on, Shelford Notts. 21st April 2014