The Gelechiidae is one of the largest families of microlepidoptera in the world and includes more than 4,600 described species referred to about 500 genera. About 865 named species in 94 genera occur in Western Hemisphere north of Mexico, although it has been estimated that this represents less than half of the total number of species in the region. Larvae have a wide range of hosts among the higher plants, and a few species are known to feed on mosses, decaying plant material, and stored products. Many species feed as leaf rollers or leaf tiers, but others feed on seeds, form galls, or mine leaves or needles. Several species are economically important in agriculture and forestry in the United States and Canada, especially those that have been introduced from other countries, e.g., Pectinophora gossypiella (Pink Bollworm), Phthorimaea operculella (Potato Tuberworm), Dichomeris marginella (Juniper Webworm), and Sitotroga cerealella (Angumois Grain Moth).
Unless credited otherwise, all photographs on these pages were made by SangMi Lee in partial fulfillment of an NSF grant for developing "A Global Framework for the Phylogeny of Gelechioid Moths" (DEB-0416078; John Wenzel and Richard Brown, Co-PIs). Specimens photographed by SangMi Lee were obtained from the Canadian National Collection, Mississippi Entomological Museum, University of California, Berkeley (Essig Museum), and U.S. National Museum of Natural History.