In 2006, the U.S. National Park Service invited the first author to conduct a 10-year study of the moths at White Sands National Monument, in the Tularosa Basin in southern New Mexico. Eucosma gypsumana (Tortricidae, Olethreutinae, Eucosmini) Metzler and Porter, new species, discovered during the study is described. Adult moths and male and female genitalia are illustrated. A graph illustrating an unexplained temporal population irregularity of E. gypsumana is presented. A list of species of Eucosma from the Monument is provided.
white gypsum dunes geologic formation