Wingspan 22-29 mm.
Occurring only in parts of Scotland, this species closely resembles two related species, C. osthelderi and C. speculalis, neither of which breeds in Britain. The commoner C. pinella can be separated by the lack of white subterminal band beyond the main central white markings.
The moth flies in July and August, and frequents pine plantations, resting during the day amongst the needles.
The life history is not well documented, but the larva probably feeds on mosses.