This week's butterfly is Heraclides andraemon, the Bahaman, or Cuban Swallowtail. It's another "giant," with some resemblance to Florida's resident Giant Swallowtails. Like them, its wingspan is usually about four inches, but individuals measuring over five inches have been found.
Like them, it can just be gorgeous with no effect on humans, but when humans plant big groves of citrus the butterflies are often tempted to eat citrus leaves and fruit. They don't kill the trees but do ruin any fruit they eat and cause alarm and despondency in citrus growers. At least the caterpillars, though large, don't travel in solid rafts of leaf munchers. They are less likely to become pests when citrus trees are planted among other useful trees that attract different species. This forces each butterfly (or moth or beetle) group to spread out and, inevitably, thin down to sustainable levels.
There are small, consistent differences among three subspecies of this butterfly, as it has evolved in three geographical areas. Each subspecies can therefore claim its own English name.
Heraclides andraemon andraemon is the Cuban Swallowtail. Andraemon was the name of several different characters in Greek literature. Probably the best known was an Aetolian king, the father of Thoas, a Trojan warrior, in the Iliad. Heraclides thoas is another giant swallowtail species found on Cuba.
These butterflies live in places that don't really have winter; generations can overlap and on any given day of the year, somewhere, one of them is flying. Thus, on the same day, Alex835 found a late-stage caterpillar. It is not showing its osmeterium. Heraclides andraemon caterpillars have a little square white yoke across where their shoulders would be, if they had shoulders. It is permanent and may discourage some predators, although the caterpillars aren't very toxic. They have osmeteria, too. Those who report noticing an odor describe the odor as "rancid."
And Alex835 also found a pupa:
Like many tropical butterflies, they mature fast, and their host plants also grow fast. However, for reasons unclear, some individuals spend a long time in their pupal shells, increasing generational overlap. Scientists can observe that asynchronous eclosion allows siblings to fly in different seasons and thus increases the chance that some of a given brood will survive and reproduce, but what causes individuals to mature fast or slowly, once they've entered the pupal stage, remains unknown.
Photo by Jahnikablair, August, Jamaica.
Heraclides andraemon is considered an introduced nuisance on Jamaica, where there is concern about its competing with native species.
http://naturalhistorysocietyjamaica.org/nature/NaturesJottings2015-10.pdf (discussion of butterflies comes at the end of the document)
Google doesn't like the actual web site for the book announcement linked here. The page linked below gives a checklist of Jamaican butterflies with plenty of Jamaican attitude toward Heraclides andraemon and advertises a full-length field guide. There's a link to the web site associated with the book, but Google refuses to open it.
Jahnikablair didn't even want to say where on the island she'd found the couple shown above. Some Jamaicans would have thought Jahnikablair should have killed them while they were still and vulnerable. Anyway, the photo documents that this species often mates in a sort of "69" position that allows either half of a couple to carry the other half away from a predator, if startled in the act of mating.
Photo by Robin_Dive_Diva, March, Cuba.
If Jamaicans don't welcome this species, they certainly have documented it. At the GBIF site, a full half of its observation records--almost 150 photos--come from Jamaica; more than Cuba, Grand Cayman, and Nassau, where the butterflies are a minor tourist attraction, together.
Hundreds of beautiful Caribbean flower photos, documenting the variety of plants Heraclides andraemon pollinates, are at
Heraclides andraemon andraemon is found on the other Cayman and Turks and Caicos islands, but not normally on Grand Cayman, which has its own subspecies. It has sometimes strayed into Florida, usually on the Keys, like H.a. bonhotei.
Heraclides andraemon bonhotei is the Bahaman (Bahamian, Bahama, Bahamas) Swallowtail. It has been known to stray onto the Florida Keys, and is believed occasionally to stray onto the main peninsula of southern Florida. It was named for John Lewis Bonhote, a British naturalist. Though the Bahaman Swallowtail was first described by Emily Mary Bowdler Sharpe, the first woman to publish a paper with the Zoological Society of London, Bonhote was the first to present actual dried and pinned specimens to the Society.
Photo by Fezzgator, July, Florida Keys.
Photo by Mgochfeld, April, Nassau.
This 1986 report (among other things) compares H.a. bonhotei with a confusible species in the Bahamas:
And Heraclides andraemon tailori is the Grand Cayman Swallowtail, found only on Grand Cayman Island. Charles B. Taylor, a Jamaican naturalist, visited Grand Cayman island in 1896 and identified this butterfly, and a bulfinch species, as being island specialties.
Photo by Caymannature, December, Grand Cayman. The golden glow on the black part of its wings is mostly an effect of the lighr.
Photo by Caymannature, apparently a different butterfly, same day.
While the other subspecies of Heraclides andraemon could probably crossbreed if they chose, tailori looks as if mating with the other subspecies would be difficult for it. That's all this web site is going to say on the subject. You can find drawings of the tail segments if you look for them online.
Photo by Caymannature, October. Only the youngest of these young caterpillars shows a prominent yoke, though the older two have some vestige of it.
Photo by Verdantisles, December, Grand Cayman.
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. Photo by Caymanmatt. Both sexes pollinate lots of pretty tropical flowers.
This island specialty has of course been featured on Cayman Islands postage stamps:
People have wanted to believe that Heraclides andraemon was native to Florida and is in danger of being extirpated...
It was on the US endangered species list in the 1970s and 1980s. It was "delisted" due to lack of proof that it's ever been a US species. It may already have been extirpated as a full-time resident of Miami or the Keys. Scientists have confirmed its existence there only as an occasional visitor.
However, at least one visiting andraemon assumed that a massive project intended to help Schaus' Swallowtail populations rebound, in Florida, was for its benefit. (Both Schaus' Swallowtails and Cuban Swallowtails can live on the wild lime trees planted for the benefit of Schaus' Swallowtails.)
Despite evidence that Heraclides andraemon is no longer a native species in the US if it ever was one, that it may compete with endangered Schaus' Swallowtails, and that orange farmers would not like to see it become established in the US, apparently conservation grants are still available for anyone who can document having it in residence on property the person wants to dedicate to its conservation. Boondoggle? Maybe. Then again, when I see these grants advertised in Idaho, somehow I don't feel worried. These butterflies are very unlikely to become pests in Idaho.
Unlike some butterflies that have only one host plant, andraemon can live on several different plants in the citrus family. On Grand Cayman, tailori originally lived on a native tree called candlewood, before orange and grapefruit trees were brought in, and still can survive on candlewood and other uncultivated plants alone. It can also live on a large tree called the shake-hand tree. Not shake-hands, but shake-hand! This photo essay is about the tree but documents its continued use as a host by Heraclides andraemon:
The Cayman Islands' government site recommends this hardcover book about the butterflies of those particular islands:
In writing these articles I've been guided by Delano St Aubyn Lewis's e-book, Phylogeny and Revision of the Genus Heraclides; despite its technical-sounding title (and some technical vocabulary) this is a readable study of the next few weeks' featured butterflies. It does include those detailed studies of the tail ends, which scientists often use to identify species that otherwise look alike, and which this web site does not go into in detail. (We may show a few images that might qualify as porn for butterflies who may read this web site, but not hard core.) It has been made available as a Creative Commons e-book and can be downloaded in PDF format from at least five sources. The link I followed first was
If you're interested in the Heraclides species who visit the southern tip of Florida, and your computer handles PDF well, you may also want to download this article, which has color photos showing the differences between H. andremon and similar-looking H. androgeus.
Finally, this Portuguese-language site offers photos of several Heraclides species for side-by-side comparison:
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