Wingspan c. 10mm.
This species has a scattered distribution across England and Wales, into parts of Scotland, and flies during July and August.
The larva feeds on wild marjoram (Origanum vulgare), occasionally on other herbs, feeding in autumn on the seeds from inside a case constructed from the calyxes of the foodplant. As it grows, the larva attaches further calyxes, resulting in a rather distinctive appearance.
The adult moths are small and whitish, marked with grey and black.