([Denis & Schiffermüller], 1775)
A relatively scarce and local species in Britain, most frequently encountered in the south-east.
Adults are similar in appearance to the commoner P. regiana, though the dorsal blotch in trauniana tends to be paler, more lemon-yellow in colour, and more uniform in shape. The costal blotches in trauniana are often thicker and yellower, though the two species can be difficult to separate in some cases without dissection.
The foodplant is Field Maple (Acer campestre), the larvae feeding on the seeds.
There is a single generation, with adults on the wing from May to July, often flying in sunshine around the foodplant.