plants, and eggs are placed singly. While leaf shape experiments and egg mimics do not have significant effects on oviposition, chemical cues from methanol render sites less appealing to H. cydno. Their lack of preference for leaf shape can be attributed to their varied usage of Passiflora hosts. H. cydno also does not participate in larval cannibalism, which plays a role in their indifference to egg mimics. Life cycle Egg The eggs of H. cydno are yellow, 1.1 mm in height and 0.9 mm wide. Larvae Early instar larvae of this species have a white body and black spines. Mature larvae are characterized by an orange head topped by two black horns 1.2 cm long. Their bodies are brownish pink, with black scoli (spines with multiple points) and black spots. The caterpillars of H. cydno are known to form small groups, demonstrating social behavior. Pupae Pupae of H. cydno are characterized by antennae, an abdomen with long spines, and a general dark brown color. They have two rectangular gold patches that decorate the thorax. Adult Adults have forewings and hindwings which are black with either yellow or white bands/spots. Their hindwings have bars on their ventral surface, distinguishing themselves from mimics. Wing coloration is dependent on location. Protective coloration and behavior Müllerian mimicry H. cydno engages in the predator defense mechanism of Müllerian mimicry with H. eleuchia (specifically in Ecuador) and H. sapho by adopting colors that warn a predator of their bad taste, deterring attacks. For instance, H. cydno alithea, which has two potential colorings, mimics H. eleuchia in its yellow form, and mimics H. sapho in its white form. In contrast, H. cydno close relative, H. melpomene, mimics H. erato. Genetics Hybridization It is a species well known and widely researched for its tendency to hybridize with the closely related H. melpomene, from which it diverged around 1.5 million years ago. They are sympatric for much of the geographic range of H. cydno, from Central America to northern South America, and exhibit a low level of hybridization and gene flow in nature. Hybrids between the two species occur at a frequency of less than 0.1%. Their low levels of hybridization can, in part, be attributed to pre-mating isolation, as H. melpone is found in more open habitats, while H. cydno lives in a closed-forest environment. Studies suggest that changes in host use and mimicry in H. melpomene and