Iridopsis Warren, 1894 (Lepidoptera: Geometridae: Ennominae: Boarmiini) is a New World moth genus mainly diversified in the Neotropical Region. It is represented in Chile by two described species, both from the Atacama Desert.
Iridopsis socoromaensis sp. n. (Lepidoptera: Geometridae: Ennominae: Boarmiini) is described and illustrated from the western slopes of the Andes of northern Chile. Its larvae were found feeding on leaves of the Chilean endemic shrub Dalea pennellii (J.F. Macbr.) J.F. Macbr. var. chilensis Barneby (Fabaceae). Morphological differences of I. socoromaensis sp. n. with the two species of the genus previously known from Chile are discussed. A DNA barcode fragment of I. socoromaensis sp. n. showed 93.7-94.3% similarity with the Nearctic I. sanctissima (Barnes & McDunnough, 1917). However, the morphology of the genitalia suggests that these two species are distantly related. The discovery of I. socoromaensis sp. n. highlights the need for additional surveys in underexplored areas to understand better the taxonomic diversity and evolutionary relationships of the mainly Neotropical moth genus Iridopsis.