Heliconius charithonia

Heliconius charithonia

The Zebra heliconian butterfly (Heliconius charithonia Linnaeus, 1767) is a moth belonging to the Nymphalidae family.

Systematic –
From a systematic point of view it belongs to the Eukaryota Domain, Animalia Kingdom, Sub-Kingdom Eumetazoa, Superphylum Protostomia, Phylum Arthropoda, Subphylum Tracheata, Superclass Hexapoda, Insecta Class, Subclass Pterygota, Endopterygota Cohort, Order Oligoneoptera, Order Epidopidae, Order Epidopata, Heteroneura, Ditrysia Division, Papilionoid Superfamily, Nymphalidae Family, Heliconiinae Subfamily, Heliconiini Tribe and therefore the Heliconius Genus and the H. charithonia Species.
The terms are synonymous:
– Papilio Charithonia;
– Heliconius charithonius;
– Apostraphiaithith Dyar, 1903.
The following subspecies are recognized within this species:
– H. c. Charithonia, Ecuador;
– H. c. simulator, Jamaica;
– H. c. bassleri, Colombia;
– H. c. Churchi, Haiti;
– H. c. tuckeri, in Florida;
– H. c. vazquezae, from Mexico to Panama;
– H. c. ramsdeni, Cuba;
– H. c. antiquus, St. Kitts, Antigua.

Geographical Distribution and Habitat –
Heliconius charithonia is a butterfly found throughout South and Central America and up to southern Texas and peninsular Florida; during the warmer months there are migrations north to other American states: New Mexico, South Carolina and Nebraska.
Its habitat is that of tropical areas, wet forests, field edges.
The geographical distribution of this moth overlaps with the populations of other butterflies which sometimes lead to conflicts.

Morphology –
Heliconius charithonia are lepidoptera which, at the adult stage, are medium in size with wingspan between 72 and 100 mm. The wings, on the dorsal side, are black with the presence of narrow longitudinal white and yellow stripes, with a similar motif on the ventral part, but paler and with red spots.
The caterpillars are white in color with black spots and with numerous black tips along their body.

Aptitude and biological cycle –
Adult males of this species mate using, for this purpose, visual, olfactory, tactile and auditory signals to reach the females during mating.
The indication on the presence of females is provided above all by host plants where females can ordinarily be found.
Adult males wait for a female to emerge from her pupa and, in an emergency, two or more males can fight to “win” the female. The winner mates with the females and prevents other males from doing it through a chemical transfer, passing a nutrient-rich spermatophore to the female which thus reduces the possibility of other mating.
Thus, females rarely participate in more than one mating for a lifetime.
Oogenesis is strongly influenced by pollen intake. When pollen is absent in the diet, oviposition rates decrease and lifelong fertility, or the number of eggs produced, decreases significantly.
Males usually stay close to their birth sites while females move to find the oviposition site on Passionflower plants. Since the females are very mobile, the males rarely mate with females with a close relationship, so the inbreeding rate is very low.
The behavior of this butterfly has facilitated the evolution of aposematic mimicry. Butterflies that feed on pollen are more unsightly for predators, more colorful and show a greater mimetic diversity than those that don’t.
The caterpillar feeds on Passiflora lutea, Passiflora suberosa and Passiflora biflora. Their nutritional intake has a balanced protein-carbohydrate ratio.
Caterpillars feed on Passionflower plants on which their mother laid their eggs. Passionflower plants have trichomes, structures that reduce the herbivorous attack physically or chemically. The larvae of this butterfly can avoid the effects of trichomes, being able to create silk carpets on trichomes, providing a surface to walk on more easily and removing the tips of trichomes by biting them. The tips of the trichoma are then found in the feces of these individuals. The larvae often try to avoid areas where the density of the trichome is higher by staying on the lower surface of the leaves.

Ecological role –
Heliconius charithonia adults rest at night in groups of up to 60 adults for greater safety from predators. Adult butterflies feed on pollen in order to synthesize the cyanogenic glycosides that make their bodies toxic to potential predators. The caterpillars, as mentioned, feed on various species of passionflower, eluding the defensive trichomes of the plants by biting or spreading them over.
Unfortunately, spraying Naled, a phosphorganic insecticide, has decimated the population of Heliconius charithonia in Miami-Dade County, Florida and other areas.
Mass collapses of the colonies have occurred with impacts on the balance of the ecosystem.
Heliconius charithonia was declared the official butterfly for the state of Florida in 1996.

Guido Bissanti

Sources
– Wikipedia, the free encyclopedia.
– Russo G., 1976. Agricultural entomology. Special Part. Liguori Editore, Naples.
– Tremblay E., 1997. Applied entomology. Liguori Editore, Naples.