Incarnadine

Pantilius tunicatus is a late season mirid bug. Most members of this family are sap suckers, though a few are predatory, and they tend to be known colloquially as plant bugs. Some species cause serious damage to commercial crops and are regarded as pests, but this one feeds on hazel, alder and birch trees, and in my garden at least it's welcome to them. In my experience it can turn up on shrubs as well, notably laurel and dogwood.

Pantilius tunicatus appears later in the year than most bugs, though I would dispute the sources that say you won't find it until September: I recorded adults here back in August, and I've found both adults and nymphs regularly since then. I'd also suggest that the received wisdom that it's always 8-10mm long isn't wholly accurate: this one was more like 11-12mm, and a quarter of an hour earlier I'd found another adult which was only about 7mm, and which I had to examine very closely to be sure that my identification of it was correct.

NatureSpot and a few other sources state that P. tunicatus may overwinter, and though I can't be sure that it does I think this is very likely, simply because both my specimens today had lost all trace of the green colouration these bugs show on their legs and wing cases when they're fresh, and were turning to the colour of leaf litter. The only way to be sure would be to find an overwintered adult in the spring, which I've never managed to do, but maybe next year I'll be lucky.