Common in damp heathland, mosses, marshes, river-banks and moorland throughout the British Isles. Widespread and common in Hampshire and on the Isle of Wight. Wingspan 10-17 mm. Distinguished from
B. furfurana by the crescent-shaped discocellular mark and the absence of a basal patch on the forewing; unicolorous specimens can only be separated by examination of the genitalia. Small specimens of
B. robustana often resemble
B. lancealana superficially and dissection of the genitalia may be necessary [Bradley]. Larva feeds within stems of Compact Rush, Common Club-rush and Deergrass.