Gracillariidae

Gracillariidae is a diverse family of small moths in the superfamily Gracillarioidea, order Lepidoptera. It contains roughly 100 genera and more than 2,000 described species, occurring worldwide in a variety of habitats, especially forests, woodlands, and cultivated areas.

Adults are diminutive moths with narrow, elongated wings that are often patterned with metallic markings; when at rest they are typically held roof-like over the body. The larvae are leaf miners, feeding within living leaves and producing characteristic mines that can be serpentine, blotchy, or tentiform. Early instars create narrow, winding tunnels, while later stages form larger mines and may cause the leaf to curl or fold. Pupation usually occurs within the mine or in the immediate leaf litter.

Ecology and life history vary by species, but Gracillariidae are generally highly specialized on particular host plants. Many species have several generations per year in warm climates, with mining activity concentrated during the growing season. Host plants include a wide range of deciduous trees, fruit crops, and ornamentals, making some species economically important as pests.

Economic and research significance varies by region and species. Notable pest examples include Phyllocnistis citrella, the citrus leaf miner, which damages young citrus foliage, and various Cameraria and Stigmella species on ornamentals and fruit trees. Because leaf-mining behavior and mine patterns are often species-specific, Gracillariidae are frequently studied in taxonomy, ecology, and pest management.

Distribution is global, with the greatest species richness in temperate to tropical regions. Gracillariidae represent a key group within leaf-mining Lepidoptera, illustrating diversity in life history strategies and plant associations.