(Living) Gem Show

This weekend is probably the peak of the annual Tucson Gem & Mineral Show, easily the largest, most economically important tourist event of the year in southern Arizona. There are so many rocks, minerals, fossils, meteorites, sculptures, and other merchandise here that I’m surprised it doesn’t tip the Earth’s axis. The scale of the exhibition defies easy comparisons and quantification. It is difficult to find any other display that rivals the gem show for color and spectacle, but perhaps the Tucson Botanical Gardens has it in the form of its annual “Butterfly Magic” exhibit of live Lepidoptera.

There are stones and tourists here at the Tucson Gem & Mineral Show from all over the globe, but there are also live butterflies and moths from all over the world at the TBG. Rocks may glitter and gleam, but they don’t fly, or land delicately on you like the insects in the live butterfly exhibit.

Among the wonders of the butterfly show are metallic blue Morpho butterflies from the Latin American tropics.

Like a living geode, they usually conceal their beauty while perched with wings closed. The underside of their wings are colored in earthtones with spots and stripes.

Sharing its name with a stone of similar color, the Malachite, Siproeta stelenes, also hails from Mexico and Central America, but can also be seen in extreme southern Florida and south Texas.

Glasswing butterflies in the family Nymphalidae, subfamily Ithomiinae, have wings as transparent as the windows of any building. No silica here, just an absence of the scales that normally give butterflies their vibrant color patterns. Only the veins and edges are pigmented here, creating artistic panes.

Not to be outdone by their day-active counterparts, some moths have a subtle beauty all their own. By any standards the African moon moth, Argema mimosae, is a glamorous animal, with tails that stream like a comet or shooting star.

No meteorite fall at the end, but an equally ephemeral life. With no mouthparts to feed, these giant moths live for no more than a few days, just long enough to reproduce.

My friends in the meteorite-hunting world have given me a new appreciation for both extra-terrestrial and earth-borne geology, but it is still difficult not to choose the living over the inanimate. Whatever your own predilection, be sure to share that passion with others. It is a great way to make new friends and expand each other’s horizons.

Behe(moths)

Most moths are not terribly large. In fact, there are many which are so small that they are collectively referred to as “micros.” Then there is the other end of the spectrum which includes some species that have the largest wing surface of any insect. At the “Moth Ball” in Athol, Worcester County, Massachusetts on June 13, we had our share of behe-moths visit the lights.

Our giant moths were all in the family Sphingidae, known as sphinx moths or hawkmoths. They get the former name from someone who thought the pose of a disturbed larval sphingid resembled the pose of the Great Sphinx in Egypt. It was probably the same person who named the constellations. I sure don’t see any resemblance. “Hawkmoth” is more legitimate, as many of the sphingids fly rapidly, even hover in front of night-blooming plants to sip nectar from tubular flowers like Datura.

The first sphinx moth to show up was this waved sphinx, Ceratomia undulosa, a bit waterlogged in this shot after a night exposed to the elements. There are five North American species in the genus Ceratomia, and all of them look very similar to this one.

This pawpaw sphinx, Dolba hyloeus, is named after the larval food plant, though the caterpillars will also eat blueberry, holly, and sweetfern.

This northern pine sphinx, Lapara bombycoides, was downright diminutive compared to the other sphingids we saw, with a wingspan of only 4.5 to 6 cm compared to the 8-11 cm span of a waved sphinx. It looks all the more bedraggled because one of our party members rescued it from a puddle.

The only other sphinx moth I was able to get an image of was one of my favorites, a blinded sphinx, Paonias excaecatus. This large insect, no doubt a wilted leaf mimic at rest, is named for the striking blue eyespot on the hindwing, exposed if the moth feels threatened. Since it lacks a “pupil” in the center of the eyespot, it was christened with the handicapped moniker. It has a very wide distribution, too. I remember collecting this species in Oregon and Ohio, as well as seeing it here in western Massachusetts.

While serious entomologists might put out blacklights and mercury vapor lamps to draw in moths, simply turning on your own porchlight will lure many an exotic-looking lepidopteran to your doorstep. Consider making a project of recording the moths that visit your property. There are many wonderful online resources to help you identify them, including Bug Guide and the Moth Photographers Group to name just two. Above all, have fun just looking.

.

Party-crashers at the "Moth Ball"

I suppose no social event is complete without the uninvited or unwelcome guests that take it upon themselves to crash the party. The “Moth Ball” was no exception. Held at the home of David and Shelley Small in Athol, Worcester County, Massachusetts on June 13, the primary attendees other than Homo sapiens were members of the insect order Lepidoptera (moths and butterflies). The lack of explicit invitations didn’t stop some other insects from making the scene anyway.

I have learned quickly that among the most abundant and annoying insects here are mosquitoes. These biting flies of the family Culicidae are not attracted to lights in large numbers, but the people looking at other insects, exhaling carbon dioxide, perspiring lactic acid, and otherwise filling the air with mosquito attractants, are sure to draw them in. This one did not come alone, either. The red spots on its “chest” are not drops of human blood, they are mites, tiny arachnids that may be parasitic, or simply hitching a ride to some unknown destination.

Mites do not restrict themselves to mosquitoes. Well, certain species of mites certainly do, but other mites ride on their version of jumbo jets, like this large burying beetle, genus Nicrophorus, in the family Silphidae. Burying beetles, also called “sexton beetles,” bury the carcasses of small animals like rodents, shrews, songbirds, and the like. They often work in male/female pairs to dig under the animal, sinking its body into the ground. There, the beetles excavate a chamber, and the female sets to work molding the corpse into a literal meatball, laying her eggs in a small crater atop the mass. She feeds the larvae that hatch until they can eat on their own, all the while grooming the food ball to keep it fungus-free, and fending off competing beetles that may sniff out her prize and try to kill her family to get it. Such parental care is rare in solitary insects. That these beetles are so boldly colored is a bonus to beetle aficionados.

Yet another intriguing beetle showed its face at the porch light as well. Maybe this male fire-colored beetle, Dendroides concolor used its “TV antennae” to home in on the action. This nocturnal insect of the family Pyrochroidae also has huge eyes, the better to see in the dark. All kidding aside, the antennae are probably used to detect the pheromones of females of his species, as she boasts much less elaborate fixtures on her own face.

At least one other group of insects was easily mistaken for moths: the caddisflies of the order Trichoptera. As larvae, they are aquatic, most living in flowing water such as streams and rivers, many of them building cases that are essentially “mobile homes” which help camouflage them and give them a place to retreat into should danger threaten. The adults are very moth-like and difficult for the casual observer to distinguish from Lepidoptera. This was one of many to join the soiree with the other insects.

Last but not least, were a few mayflies, order Ephemeroptera. They may have been fashionably late (the Moth Ball was in June, after all), but they literally showed up in coats and tails, their filamentous cerci streaming behind them from the tip of their abdomens.

Mayflies are unique among all insects in that they molt after reaching adulthood. A “subimago,” prounounced sub-im-ah-go, emerges from the last larval skin of these aquatic insects, and then molts into a full-blown “imago” shortly thereafter. Their appearance at the Moth Ball may have been their only fling. Mayfly adults can live as short as one day, and probably not much longer than 2-3 days, just long enough to reproduce. Their youth, however, can take years in the case of some species, living as aquatic larvae (aka “naiads”).

Hopefully all these diverse insects found the party as entertaining as we did just watching them milling about in the rain. There is certainly no boredom to be found in the world of entomology.