Napeocles jucunda (Nymphalidae: Victorinini) has blue wings more reminiscent of canopy-flying Charaxinae (Nymphalidae) than its phylogenetic relatives Siproeta and Anartia, which live primarily in forest edges and disturbed areas. Here, we present photos and descriptions of its immature stages and host plant (Ruellia sp. nov. (Acanthaceae)) from northern Peru, together with remarks on adult behavior. Taken in conjunction with previously published data from French Guiana, our observations suggest that color pattern divergence in N. jucunda has been accompanied by specialisation on scandent host plants, and flying in the mid-story and canopy of forests. We discuss hypotheses for the adaptive significance of blue wing patterns in such environments.