Wingspan 22-27 mm.
The easiest of the three British species of Phycitodes to identify; it is the largest, and has large blackish dots on a paler ground colour. The resting posture where the wings are rolled tightly around the body is common to the group.
It occurs throughout England and Ireland, but is not especially common.
The larvae feed inside the flowerheads of spear thistle (Cirsium vulgare)
The single generation flies in July and August.