Elachista freyerella

The wingspan is 7–8 millimetres (0.28–0.31 in).The head is dark grey, whitish-sprinkled, face paler or whitish. Forewings are blackish, somewhat paler-sprinkled ; an oblique fascia before middle, in male indistinct and sometimes interrupted, a tornal spot, and an opposite costal spot (appearing together to form a perpendicular interrupted fascia) whitish, in female whiter and more distinct. Hindwings are grey. The larva is pale yellowish-grey ; head black or pale brown ; 2 with two black spots[2]

The larvae feed on bent (Agrostis species), bromes (Bromus species), cocksfoot grasses (Dactylis species), tall fescue (Festuca arundinacea), red fescue (Festuca rubra), soft grass (Holcus), crested hair-grass (Koeleria macrantha), annual meadow grass (Poa annua), Poa badensis, wood bluegrass (Poa nemoralis), common meadow-grass (Poa pratensis), rough meadow-grass (Poa trivialis), Trisetum ciliare and Triticum. The larvae create a mine consisting of a long, flat, whitish, relatively broad corridor descending from the leaf tip. A single larva may make several mines during its lifetime. Pupation takes place outside of the mine.[3]