Micromoths, or microlepidoptera is a group of moth families. They are very common, but much smaller than the more familiar butterflies and moths. They have wingspans of under 20 mm, and are hard to see well enough to identify.
They have some lifestyles different from the larger lepidoptera, but this is not an identifying mark. The group is not monophyletic, so the term 'micromoth' is just a convenient label. It can be contrasted with macrolepidoptera, the larger types.