H. melpomene looks nearly identical to its co-mimic H. erato (see photo below for how tell them apart). They also occupy similar second-growth habitats, where they each search for their preferred host plants. H. melpomene is specialized to lay her eggs on P. oerstedii and more rarely, P. menispermifolia. Although these plants have very different habits and chemistry, they both are closely related in section Granadillastrum (subgenus Passiflora) and they both possess several pairs of tiny stalked nectar glands on the petioles. These glands are not very attractive to ants, but those of P. oerstedii (and perhaps P. menispermifolia) are apparently attractive to microhymenopteran egg parasitoids. Range: Mexico to Brazil.

Like its close relative H. cydno, H. melpomene larvae are capable of feeding successfully on many species of Passiflora, including Decaloba species such as biflora and auriculata. I have suggested that perhaps H. melpomene specializes on P. oerstedii (and possibly P. menispermifolia) in order to avoid predation by ants that are attracted to other Passiflora species (Smiley 1978 a,b).