Eligmodontia morgani Allen, 1901, is a sigmodontine rodent commonly known as the western Patagonian laucha. A small, delicate, arid-adapted rodent, it is 1 of 7 currently recognized species in the genus Eligmodontia. The species occurs in the semiarid steppe habitat of western Patagonia of Argentina and Chile. E. morgani is listed as “Least Concern” by the International Union for Conservation of Nature and Natural Resources.