The adult is a small delicate moth with snowy white wings speckled with pale brown markings.The insect is a problem in all the rice tracts of the State. The eggs are laid on both the surfaces of leaves and leaf sheaths.The young larvae move in to the water droplets on the leaf and start feeding by scraping the green matter. As the larva grows it makes leaf folds and cut it loose from the leaves.The caterpillar remains in this chamber and moves with the case and actively feed on the leaves.Tubular gills are present on the body of the caterpillar.Caterpillar can breath only from water with the help of tracheal gills.This is why the pest infestation is found in fields with standing water.The larval cases contain water to enable the larvae for breathing. Dispersal of larva takes place by floating on water.
Total life cycle from egg to adult takes about 5 weeks- with egg period 5-6days and larval period 20 -22 days.Full grown larva pupates in the last case it makes after attaching it to the leaf sheath above the water level.