Clepsis anderslaneyii, new species is described and illustrated from the “sky islands” (i.e., Chiricahua, Huachuca, and Santa Rita mountains) of southeastern Arizona, U.S.A. Superficially, it is most similar to Argyrotaenia dorsalana (Dyar 1903), but it is assigned unambiguously to Clepsis Guenée on the basis of the characteristically modified transtilla, which includes a narrow or obsolete mesal portion and a dentate subbasal swollen lobe. Among Nearctic congeners, the male genitalia of C. anderslaneyii are most similar to those of C. fucana (Walsingham 1879), but those of C anderslaneyii can be distinguished by the more broadly pointed valva, narrower transtilla, bulbous uncus, and broader tegumen. The extremely short ductus bursae of the female genitalia of C. anderslaneyii is unique among Clepsis.