Eriocraniidae

Eriocraniidae is a small family of moths, commonly known as "jewel moths" or "fairy moths". These moths are among the most primitive living moths, possessing unique characteristics that link them to ancient moth ancestors. They are found primarily in temperate regions of the Northern Hemisphere, with a notable diversity in Europe and North America. Adult eriocraniids are generally small, with metallic scales on their wings that give them a shimmering appearance. Their antennae are often filiform or slightly pectinate.

The larval stage of eriocraniids is distinct. They are leaf miners, creating serpentine mines within the leaves of deciduous trees, particularly oak, birch, and hazel. The mines are typically characterized by their frass pattern, which can be a key identification feature for different species. The larvae have a chewing mouthpart and feed on the mesophyll tissue of the leaves.

Eriocraniidae are considered holometabolous insects, undergoing complete metamorphosis. After feeding and growing within the leaf mine, the larva eventually exits the mine and spins a cocoon in the soil or leaf litter to pupate. The adult moths emerge in the spring and are typically short-lived, with a primary focus on reproduction. Their primitive features, such as chewing mouthparts in adults (though reduced in most species) and a simple wing venation, make them of significant scientific interest for understanding insect evolution.