The University of Texas at El Paso Biodiversity Collections (UTEP) Invertebrate Collection is comprised of recent and fossil specimens, mostly dried shells. About 70% of the materials are terrestrial gastropods, 25% freshwater molluscans (including unionaceans), and 5% marine forms. Geographic coverage is mostly for New Mexico (about 80%), but there also are significant holdings for Kansas, Mexico, Oklahoma, and Texas. This taxonomic and geographic composition has arisen because of the principal research interests and activities of Artie L. Metcalf, and his students.