Length 11 to 17 mm. A very pale species, often with a greasy appearance. Forewings narrow with an almost straight front edge and sharply truncated at the tip. Individual species are difficult to distinguish.
It is a species whose larvae can be found in lakes, ponds and pools. Its substratum preference includes plant material, particulate organic matter, sand and gravel, in standing and slow-flowing water mainly in small ponds. Limnephilus flavicornis has a case made from thin sections of plant material arranged in a criss-cross fashion. Its larvae can occur in brackish water and shows no preference for pH.
In temperate areas, Limnephilus flavicornis has a univoltine (one generation per year) reproductive cycle. Adults can be found on the wing from May to November, with a summer diapause.
