these "micromoths" are generally of slender build, and like in many of their relatives, the margins of their wings usually consist of a "fringe" of hairs. the tiny caterpillar larvae initially feed internally on the leaves, flowers, or seeds of their host plants. when they emerge to feed externally, they usually construct a protective silken case, discarded and built anew as they grow and molt. the common names of the coleophoridae refer to this habit.