The moth may be found in wet, marshy areas on peat. It is very locally distributed throughout the British Isles, most frequent in western Scotland and western Ireland.
The species is univoltine, flying from June to early August.
The larva is greyish-green with a black head, and mines Carex species, particularly Carnation Sedge (Carex panicea) and Common Sedge (C. nigra), in May and June.
Mining is initially from the base to the tip of leaf without crossing the midrib, and then mining down the opposite side of the midrib. The mine is gradually widened and filled with dark frass.