Wednesday, July 29, 2020

Polydamas Swallotail

The Polydamas Swallowtail, Battus polydamas, is named after both historical and mythological figures from Greek history. Battus I founded the colony of Cyrenaica and its capital Cyrene on the coast of present-day Libya around 630 BC. Impressive ruins are all that is left. 

Polydamas figures in the Illiad as an advisor and friend of Hector. Polydamas of Skotoussa, who won the Olympiad in 408 BC, was an athlete of prodigious strength. Some of his feats appear on Greek pottery. The subspecies that occurs in Florida is Battus polydamas lucayous. I haven't been able to find a reference for "lucayous." 

The polydamas is the only swallowtail in the U.S. that doesn't have tails. This butterfly is sometimes called the gold-rimmed swallowtail as well for the row of yellow patches on the edges of its wings. Their larval food are pipevines, species of Aristolochia. In our yard they feed on the exotic Giant Aristolochia, and this year pretty well denuded the massive vine.

One year, when I didn't have any caterpillars I "imported" a batch from a friend about 25 miles north of me whose polydamas larvae were on the point of starvation after completely stripping  her Aristolochia plants.

 (The pipevine swallowtail, which also feeds on Aristolochia species, looks quite different. It has short tails, and it's deep black wings are brushed with bright blue iridescence. It has creamy patches near the margins on the upper wings, and large, bright orange patches on the undersides. It does not make it quite as far south as Collier County).

The polydamas is a strong, vigorous flyer, with a rapid, almost "nervous" wingbeat. I never have seen one basking. Even when nectaring, they keep up their fluttering, and I wonder whether they may actually feed on the wing like hummingbirds now and then. The ones in our yard fly about 5-10 feet off the ground when patrolling, swooping down mainly to lay eggs or take a sip of nectar.




Polydamas Checking Out Pipevine
Notice Yellow-Jacket Patrolling lower left


This is the best year for polydamas swallowtails in our yard for a long time. The last few years a few adults have showed up, some even laying eggs. But predators seemed to clean out the caterpillars, and repeat appearances by adults were rare.

This year I noticed the first polydamas in early May, and they pretty much stayed with us through mid- July. After about a week of no sightings, I see a brand new adult as we near the end of the month. Some of the adults who emerge probably stay here, but timing of appearance suggests that I also have had some visits by newcomers.

 I have seen polydamas swallowtails here as early as late February and as late as mid-November. They range up to north-central Florida, but may stray farther north. A subspecies occurs in coastal south Texas. Otherwise, they inhabit the Bahamas, Carribean Islands, southern coastal Mexico, Central America, and south to Argentina in South America. There are many sub-species.




Polydamas Swallowtail


The above quick and dirty, and not neurotically accurate color pencil drawings were made from a battered dead specimen I picked up years ago. I'm  not at all happy with the brown undersides. I tried layering different colors, but still did not pick up the elusive, reflective warm brown/black coloration.

The female lays a cluster of orange-yellow eggs on tendrils and tender young leaves. At first the caterpillars stay close together. There must be some evolutionary advantage in this behavior, but it also makes them very vulnerable to predators. A wasp can wipe out a brood in a matter of minutes. When they get about 3/8 to 1/2 inches long they go their separate ways.



Ovipositing Female



Young caterpillars are orangish tan to brown, with many bristles. The older caterpillar looks like a fat brown slug with orange tubercules protruding from its body. The larvae absorb toxins from the aristolochia, so they are distasteful to birds and lizards. But nothing saves them from hornets.

Too many times, I have watched a yellow-jacket methodically hunting the larvae amid the leaves and devouring them one after the other. All that is left is a little puddle. I'm lucky if even one or two individuals in some broods make it to adulthood. I  have had 3 sets of egg-laying so far this years, and apart from the first brood, the yellow-jacket has been there every day looking for prey. I'm hoping it  missed one here and there, but a successful brood may depend on timing with the emergence of adult  wasps. I just don't know. The interrelationships in the natural world are so complex. And we may be getting a distorted view of it on our tiny 60x110-foot plot.

The caterpillars are sort of dumb, even for creatures that low on the intellectual ladder. I've seen more than one start eating the stem between it and the plant, and then plop down to the ground once it has severed the connection. It doesn't seem fatal, though.



Polydamas Caterpillar



One year I got fed up with the yellow-jacket's gluttony and brought several caterpillars onto the screened patio. I cut new Aristolochia leaves and stems for them faithfully, but something went terribly wrong. None were able to form a complete chrysalis, and one never got beyond the J-stage. I don't know whether I deprived my larvae of some vital nutrient by feeding them cuttings, or whether they contracted some kind of disease. Now, even though the predation distresses me, I just leave nature to take its course. Besides, the yellow-jacket feeds its larvae with liquified caterpillars, and there's a place for them, too.

Butterflies usually leave the host plant to pupate, but I have found a lot of chrysalides tucked in along the vine. They resemble twisted leaves, dead or alive - some are green and some are brown with orange markings. They are very "architectural," and remind me of miniature sets of armor. The brown chrysalis in the sketch below has been parasitized. The spot that looks like an eye is the hole from which the parasite emerged. The chrysalis may hang vertically or horizontally.



Polydamas adults are particularly fond of the weedy Madagascar Periwinkle(Catharanthus roseus) that has been in south Florida most likely for centuries. It flowers at the end of the stems, and doesn't start blooming before it is pretty tall. The stems quickly get 3 feet tall or more, and it takes no time at all for them to lose a lot of leaves along the way, and look leggy, scraggly and bare. That's when I cut them all the way back. By the way they show up in the yard, they produce plenty of viable seeds. I also have a pinkish-magenta form, which the polydamas likes too. The center of the white ones usually is dark rose-magenta, but also can be green-yellow. The center of the pink ones is a dark rose.

A member of the dogbane family, Apocnyaceae, Madagascar periwinkle is quite poisonous. It is a prime exhibit for the argument of preserving plants, for potent anti-cancer drugs have been developed from its sap. While it is a ubiquitous escape in Florida, it hasn't been classified as invasive. I hope it doesn't reach that status because many kinds of butterflies love it, and it provides clumps of cheerful, clear whites and pinks all through the year. It actually is endangered in Madagascar, its place of origin.


White Madagascar Periwinkles


When I was taking high school biology I laughed at the naivety - even stupidity - of the early theory of "spontaneous generation" to explain how animals originated. But when it comes to establishing a pollinator garden in the world of tidy, chemically-coddled suburban lawns, the possibility doesn't seem that far-fetched. Just plant some flowers, preferably natives, get some larval host plants established, and the butterflies, bees, flies and wasps show up. How they found and find me still seems pretty magical. Sadly, in the 26 years we've lived here, the sheer numbers and the number of species have declined, but I'm not giving up just yet.

Good Sources of Information:

Emmel & Kinney. Florida's Fabulous Butterflies. World Publications. 1997.

Gerberg & Arnett. Florida Butterflies. Natural Science Publications. 1989.

Glassberg, Minno & Calhoun. Butterflies Through Binoculars: Florida. Oxford University Press. 2000.

Hall. Polydamas. entnemdept.ufl.edu/creatures/bfly/polydamas. This article is particularly informative. I tried to create a link, but had no success. You can find the article just by searching "polydamas" and scrolling to it.

Minno & Minno. Florida Butterfly Gardening. University Press of Florida. 1999.

Tuesday, July 7, 2020

Spanish Stopper

June has come and gone, and I can't say where it went. The first half of the month was very wet, and the second half was unusually hot, with heat indices hitting 3 digits by 9 AM. Salt-water mosquitoes also were abundant, but I try not to complain about them because they are so important in the food chain. Probably not so coincidentally, we had lots of dragonflies too.

The yard just erupted with flowers, butterflies, new growth and new weeds. I'm hoping for cooler temperatures so l can restore some order there as well as resume outdoor sketching. Instead of trying to catch up, I am just going to jump in where we are now, with Spanish Stopper in full bloom. This year's flush is probably the best we've ever had, so I'm hoping for a lot of berries.


Delicate, Ephemeral Flowers of Spanish Stopper


Spanish Stopper (Eugenia foetida) is a shrub or small tree to about 20 feet tall in the Myrtle family. It is native to southern Florida, somewhat farther north along the state's east coast, the West Indies, Bahamas, and Central America. Despite its name it does not have a fetid odor, in or out of bloom.  Some sources claim the flowers of Spanish stopper smell unpleasant, but I can detect only a faint odor, and it's not at all unpleasant. The same goes for crushed leaves. Pruning cuts do stink for a few hours.


Eugenia foetida, habit


So I either have an outlier, or the species name foetida is a misnomer. The stink honor goes to the white stopper (Eugenia axillaris), whose leaves emit a pronounced skunky odor, which is picked up and transported by the breeze. Oddly enough, your neighbor down the street is more likely to notice it than you would standing right by the plant.

Spanish stopper has a very upright, rather than outward-spreading form, so it is good for small or tight spaces. The leaf posture accents this impression, because the leaves often are held upright, with the lower ones overlapping those higher. You may see more leaf undersides than topsides because of this ascending habit. In "botanese" the leaves are "obovate," which means that the bases are quite narrow while the tips are broad and rounded. Spanish stopper is the only one of our native stoppers whose leaves do not come to a sharp point at their tip.

Leaves are opposite, have quite short petioles, and smooth margins. Veins are not very noticeable, with only the midrib prominent on the underside. The leathery leaves are dark green on the top side, and a lighter, somewhat gray-green on the underside.




The bark is gray to brownish-gray, with newer twigs somewhat rusty in color. It is not deeply fissured, but the closely-spaced leaf scars make good "hold-fasts" for lichens and bromeliads.

Flowers appear in the angles between branches. Up close the small blooms are spectacular, with 4 white petals and numerous long stamens. At first glance they appear to be stuck directly to the branches, but if you look closer you'll see that they grow from tiny stems. The buds resemble miniature golf balls set on tees. The flowers do not last long, and the blooming season is  short. In only one or two days, the ephemeral white flowers are already shriveling. But if you are lucky enough to catch it at the right time, a Spanish stopper in full bloom, with masses of delicate snowy white flowers wreathing the stems, is truly beautiful. The fruits are globular, turning black when ripe, and are attractive to birds.


Spanish Stopper Flowers


Though our stopper is putting on its quiet show now, blooms actually may appear throughout the year. Blooming may be triggered by rain after a dry spell, or warmer weather after a cold snap.

Spanish stopper is a pioneer hammock plant, and well-suited to Florida's highly alkaline soils. Once established it is absolutely bullet-proof. I rarely water ours, and it never has shown any signs of insect or disease infestation. Though it isn't spectacular, it does have its place in the landscape as a trouble- free evergreen with wildlife appeal. It can be pruned to any shape or height desired.

Like its relatives, it derives its name from accounts that a tea made from its leaves or berries effectively treated diarrhea.