Adult : 10-14mm long (when at rest), wing span 20-24mm, grey-black forewings with dark transverse lines and outer band pale and wavy ( E. cautella), outer band pale and bordered on both sides with dark lines (E. elutella). Larvae : caterpillar-like, 15-20mm, white, or pinkish/greenish, with brown head , with clearly defined forelegs, pro-legs and setae (hairs).

Egg (100-150) individually laid on the under surface of leaves or on exposed tubers. Pupates in a silken cocoon among thrash, clods of earth, on ground, on seams of bag and in the crevices in the floor or on walls.

Adults do not feed and have a typical circular flight during dawn and dusk. The larvae or caterpillars feed on flour, bran, whole meal, flakes, grain, nuts, etc. and are serious pests in flour mills where their webbing often clogs machinery, sometimes causing shutdown.