Fairy longhorn moths, in the family Adelidae, compose a family of monotrysian moths (monotrysia ==> female has a single genital opening for mating and laying eggs ... in contrast with most other Lepidoptera) within the Order Lepidoptera.  These moths are widespread across the world, especially across North America and Eurasia.  They are considered rather primitive "micromoths"... and all of the species are rather small in size, with wingspans ranging from 4 to 28 millimeters.   The males of many of the species have especially long antennae, sometimes 1 to 3 times as long as the forewing.

The Three-stripe Longhorn Moth (Adela trigrapha) is a common, but easily overlooked, diurnal (daytime active) moth that can be found in the grassy-forb, meadow, areas in the oak woodlands of Mendocino County. They are common right now at the UC Hopland Research & Extension Center.  The three-stripe longhorn is one  of two Adela species having three white bands on the forewing ... the other being the Adela eldorado species.  These fairy longhorn moths feed in sunshine on nectar from a variety of wildflowers.