Mimicry is a defensive strategy that helps prey avoid predation by resembling unprofitable species. Due to the prevalence of mimicry in many butterfly genera, visual discrimination is especially important in identifying conspecifics for reproduction. We investigate the visual system of Adelpha fessonia, a nymphalid butterfly belonging to a diverse genus that possesses multiple mimicry complexes. Using eyeshine, epi-microspectrophotometry, optophysiology, spectroscopy and RNA-Seq data, we found no evidence of red-green color vision in A. fessonia as their eyes do not have the necessary two long-wavelength-sensitive opsins or filtering pigments. We quantified the expression levels of the mRNAs of visual opsins along with other opsin-like proteins to determine their level of involvement in vision. With transcript per million assays, we found that the ultraviolet, blue, long-wave, and unclassified opsins were highly expressed in A. fessonia head tissue while RGR-like opsin and pteropsin were not. The distribution and abundance of the blue-absorbing opsin across the A. fessonia compound eye were examined using immunohistochemistry. Phylogenetic trees consisting of various Adelpha species were created from opsin alignments and tests for positive selection for each protein were performed. Our results reveal characteristics of A. fessonia eyes which can be compared to other Adelpha and nymphalid species. Examining visual systems of individual Adelpha species is integral to understanding how color vision has diversified over time in mimetic species.