As we've seen, many Kite Swallowtails look similar to our beloved Eurytides (or Protographium or Neographium or Boreographium) marcellus. Jamaica's Kite species, which is rare, even has a Latin name that celebrates the resemblance: Eurytides marcellinus. To do online research about this butterfly requires searching for both Eurytides and Protographium, though many nature sites use both names and will show on both searches.
Here, for purposes of comparison, is a display of museum specimens of four Caribbean Kite Swallowtail species that could easily be mistaken for North America's Zebra Swallowtail, but are different. In fact, some experts think marcellus is distinctive enough to belong in a separate genus. Our Zebras can't hybridize with any of these zebra-striped foreigners:
There is, therefore, no excuse for the Fish & Wildlife Service's confusingly listing "Jamaican Kite" as an English name for the Zebra Swallowtail. Marcellinus and marcellus are two different animals; some person more focussed on office politics than on doing good work just confused them at https://www.fws.gov/species/zebra-swallowtail-eurytides-marcellus .
Though marcellinus is an adjective meaning "pertaining to Marcellus" in Latin, it was also used as a name. In the tradition of Swallowtail species names referring to heroes of literature, marcellinus can be said to commemorate any of several characters in Roman history and fiction, including an early Christian. When I searched the Web for information about the butterfly, search engines separated, but kept reminding me of, the Catacomb of Marcellinus and Peter as a tourist attraction. But nobody claimed that the butterfly name had anything to do with the saint as distinct from other ancient Romans called Marcellinus.
Photo by Vaughn Turland, co-author of Discovering Jamaican Butterflies.
Some lepidopterists have identified this butterfly with Graphium sinon, an Indian butterfly that can look similar.
By Jamaican standards it's a small Swallowtail, with a typical wingspan barely over two inches.(A Puerto Rican site, noting that some individuals measure three inches or more, calls it a large butterfly. Size is relative.) Jamaica's other native Swallowtail species are much bigger--in fact they include Papilio homerus, the biggest butterflies in the Western Hemisphere. Homerus and marcellinus eat different plants in the same forests and may be seen on the same tours. .
Photo by Susan Koenig, documenting that some individuals, in some lights, can iridesce as blue as the Blue Kite. Others look white, pale green, or yellow, all with black stripes. On museum specimens, the scales that could iridesce blue, green, yellow, or white fade to pale tan, while the black ones fade to brown.
Jamaican Kites were, like other Kites, overlooked as attention was taken up by the bigger Swallowtails, until people noticed that, due to human population spreading into their breeding territory, there were fewer Jamaican Kites than there used to be. Flying once or twice a year, these butterflies were said to "swarm" in Kingston in the twentieth century. Then they became rare. They are one of the monophagous species that can exist only in strict proportion to their host plants. As native plants were displaced by human habitat, marcellinus became rare, a Vulnerable Species. Turland believes the species' plight is even more dire than "vulnerable" and the species should be listed as Endangered.
The demand for lances is not great nowadays, so are the little trees on which these butterflies live now considered ornamental, or even "weeds"? No such. They are prized as making ideal props for vines, such as the yam vines that are an important cash crop in Jamaica, and some people are calling for legal protection for the trees as well as the butterflies.
It's easy for butterflies that breed on one Caribbean island to stray to a neighboring island. Cuban and Puerto Rican species are predictably found on the Florida Keys and might be reared in Florida. Jamaican butterflies are less likely to enter the United States. Nevertheless, the US government has been petitioned to declare marcellinus an endangered species in order to protect any individual butterfly who might manage to reach Florida or Puerto Rico. In 2004 two entomological societies actually went to court to demand that the US Fish and Wildlife Service protect marcellinus and six other "foreign butterflies," none of which FWS has the authority to do much to protect.
Such petitions have been the subject of serious deliberation; several FWS documents discuss the status of marcellinus. The species meets the criteria for being listed as endangered in the US but its listing was considered to be a low priority, for the United States, because the butterfly does not actually live here. Despite the good international relations that allow frequent travel between the US and Jamaica, Jamaica is still, like Canada, a separate nation. Confusion may have arisen because a place in Jamaica where the butterflies have been found shares the name of "St Thomas" with a different island that belongs to the United States.
Nevertheless, this PDF is an informative first book on the species despite its lack of illustrations:
https://ecosphere-documents-production-public.s3.amazonaws.com/sams/public_docs/publication/4131.pdf
Jamaicans, meanwhile, debate how to protect the butterflies' breeding territory on their island. The area where marcellinus is known to breed is near enough to the ocean to be threatened by hurricanes and tsunamis. (If "rising sea levels" were happening, the way Al Gore claimed thirty years ago, this butterfly might already be extinct.) Another area where adult butterflies hang out, and are suspected of breeding, is a strip of forest land known as "Cockpit Country," not from any association with aviation but with unsupervised human activities including making animals fight so that people could gamble on the outcome. Pits have actually been formed in this forest by bauxite mining and, while some human encroachment on the forest reportedly consists of people trying to live on the land, Jamaicans describe the place as dangerous; farmers or hippies just might fall into a pit in the crumbling limestone. Or be pushed, apparently, by those who want to preserve the forest as a place to grow illegal crops. This forest is now reportedly being regulated as habitat for marcellinus and for homerus, with results to be determined.
Though not quite as blue as celadon, marcellinus is also sometimes called a Blue Swallowtail, or Dark Zebra Swallowtail. It has been found on a few other Caribbean islands, and Puerto Rico has even tried to claim it as "Puerto Rican Kite." Each of those names, however, creates confusion by being used to refer to other species. None of the other species is called "Jamaican Kite" so that is probably the best English name for marcellinus.
The life cycle of marcellinus is weather-dependent, tied to the growth pattern of Oxandra lanceolata. Most butterflies fly in May and June, when this shrub puts forth fresh young leaves. Caterpillars eat a few leaves, then pupate among the leaf litter on the ground below their host plants. If there has been enough summer rain to stimulate fresh leaf growth in October, some butterflies will eclose in October while others wait till next May or June.
Adult butterflies don't avoid each other and can appear to form loose flocks as several individuals pollinate the same flowers. They have a favorite flower, not lancewood but another Jamaican specialty, but they pollinate several kinds of flowers. Both sexes drink fresh water at puddles. Males are more likely to slurp up mineral-rich fluids from polluted water or fresh dung; this seems to be one of the species in which females occasionally become desperate enough to do a little of this composting for themselves, but normally depend on males to supply minerals to them. (Butterflies' complicated, alien reproductive systems include mechanisms that transfer nutrients to the female along with sperm. Exactly how these mechanisms work, few humans want to know. Anyway the system allows males in many butterfly species, especially Swallowtails, to do all the dirty work of being composters while females are normally only pollinators.)
Eggs are laid on lancewood leaves, one egg to a branch, and resemble other Swallowtail eggs: tiny beads, just visible to the naked eye. Eggs can hatch within 60 hours after being laid, making this one of the few butterfly species in which parents live to see their own caterpillars, but no special family ties are observed either between mates or between parents and offspring.
Caterpillars eat lancewood leaves and grow through five instars before pupation. The trees aren't very tall and the caterpillars seem to avoid the very tops, so they are often found at about the height of a researcher's head or hands, 1 to 2m above the ground.They can be less than one inch long, or almost an inch and a half long, in their final caterpillar skins. Their colors vary, being classified as green, brown, or black. Eric Garraway has photos:
They have osmeteria, the "stink horns" all Swallowtail caterpillars seem to have, but researchers found this species relatively hard to provoke to display their osmeteria.
Pupation can be completed in a week or prolonged for most of a year. Pupae lie on the ground and respond to rainfall, eclosing quickly if there is any danger of floods, resting in the pupal state if there is any danger that their host trees will not be producing fresh new leaves when they start producing eggs. This weather-dependent state is even more precarious for the adolescent butterfly than pupation is in other species. Even before populations of marcellinus began shrinking, weather conditions produced boom and bust years for this species. Some years many butterflies survived pupation, and some years only a few did.
So it appears, in the present state of scientific knowledge, that this is a species that could potentially go extinct at any time, in any case. Still, nobody wants to be the agent of this pretty butterfly's destruction. Reporters felt that most Jamaicans are willing to leave the lancewood trees for the butterflies.
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