Frosted elfins (Callophrys irus Godart) are a rare lycaenid currently being assessed for potential listing under the US Fish and Wildlife Service's Endangered Species Act. We recorded observations on the early life stages of C. irus in north Florida as part of a larger multi-year study of a C. irus metapopulation. Oviposition was observed as early as February 20 and as late as April 7, and occurred primarily on immature inflorescences, apical shoots of a non-flowering stem, leaf petioles, leaf buds, and the margins of leaflets. Larvae were observed as early as March 18 and as late as May 11. Different larval stages fed on different portions of their host plants. The frequency of ant associations with C. irus larvae was similar to other lupine-feeding populations, but less than wild indigo-feeding populations. Larval feeding sign was useful for focusing larval search efforts and may be valuable for researchers trying to determine presence or absence of species in areas that cannot be systematically surveyed for adults.