Flying Ants

I recently came across a male specimen of the "legionary ant" Neivamyrmex nigriscens while walking our dog in our Colorado Springs neighborhood. It was instantly recognizable to me, but it got me thinking about how most people would be hard-pressed to know what it was. Unfortunately, there are very few references for the identification of winged ants. This is a shame because it is often the "alates," males and winged queens, that are most obvious to the public.

Male Legionary Ant, Neivamyrmex nigrescens, Colorado

Indeed, worker legionary ants are mostly subterranean and nocturnal in their habits (nomadic, raid the nests of other ants to prey on the larvae and pupae), so hardly ever observed by the average person. Meanwhile, a homeowner may not notice he or she has an ant "problem" until the colony swarms, liberating a cloud of alates.

Alate queen carpenter ant, Camponotus sp., Colorado

Alates are typically larger than the worker caste of wingless, sterile females, so are more noticeable for that reason as well. In many cases, the winged reproductives resemble the workers in general appearance, but this is not always the case. The thorax of winged ants is frequently greatly expanded to accommodate the muscles that operate the wings, giving males in particular a distinctive "hump-backed" appearance.

Male carpenter ant, Camponotus sp., Massachusetts

Swarms are usually seasonal, and triggered by changes in day length, relative humidity, and air pressure, especially in the arid southwest U.S. where the onset of the monsoon rainy season sparks many ant species to swarm. These emergences can be spectacular events. Worker ants open new exits from nests in the soil, and scour the immediate vicinity to rout any potential predators and parasites.

Red Imported Fire Ant swarm, Solenopsis invicta, Georgia

Many swarm events take place in late afternoon, at dusk, after dark, or at dawn. Winged ants may be attracted to outdoor lights, which can lead to the assumption that the ants came from the house or building when that is not necessarily the case.

Colonies of a given species in a localized area swarm simultaneously such that members of different colonies can find each other and increase genetic diversity while decreasing the potential for inbreeding. Winds, and the insect's own muscle power, can take the ants far from their colony of origin.

Rough Harvester Ant swarm, Pogonomyrmex rugosus, Colorado

How do you know whether it is a winged ant or a winged termite? Please read my post on termite swarms for a concise explanation, and images of winged termites. Below is an image of a winged termite to compare to the ants illustrated here.

Alate dampwood termite, Zootermopsis laticeps, Arizona

What about wasp versus ant? That is a more problematic distinction, but most ants have distinctly "elbowed" antennae, whereas wasps often do not; or at least the first segment of the antenna is not as long as it is in ants. There are exceptions, of course, like the male Neivamyrmex ant shown at the top of this post that has no obvious elbow in the antennae.

Male Pavement Ant, Tetramorium sp., Colorado

Fortunately, I am not the only one who recognizes the need to pay more attention to alate ants in terms of research and public awareness. Laurel Hansen and Art Antonelli include a key to alates in their publication, listed below. Brendon Boudinot, in a guest post for Alex Wild's Myrmecos blog, extols the virtues of studying male ants for a clearer understanding of the phylogeny of the family Formicidae.

Alate queen thatching ant, Formica sp., Colorado

Sources: Boudinot, Brendon. 2013. "Male Ants Demystified," Myrmecos.Hansen, Laurel, and Art Antonelli. 2011. Identification and Habits of Key Ant Pests in the Pacific Northwest. A Pacific Northwest Extension Publication 624. Pullman, WA: Washington State University. 14 pp.
Houseman, Richard M. 2008. "Ants." University of Missouri Extension.

Caught on the Wing

In the nearly two years I have been taking digital images of insects, I have managed to capture, largely be accident, a few insects in flight. The resulting images reveal that insects are far from fragile, but definitely agile.

For every shot I get of an insect winging its way out of the picture frame, I get at least as many of flower without fly, or rock without wasp, the perches long since vacated by the insects, if that only means by a millisecond. And that happens when I’m trying to capture an image of a stationary insect!

unidentified fly

I can’t imagine trying to capture insects in flight on purpose, but that is exactly what some photographers have been able to do regularly. Stephen Dalton, and English naturalist and photographer, was perhaps the first to successfully document different insects in flight. His book Borne on the Wind (Reader’s Digest Press, 1975) remains a classic. Another Englishman, Dr. John Brakenbury, published Insects in Flight in 1992 (Blandford, a Cassell Imprint). Both men achieved their success under largely controlled circumstances, rather than outdoors in “the wild.” Still, the resulting images are breathtaking, and highly informative about the physics of insect flight.

I’m happy to simply communicate the fact that some insects *can* fly. Many people are unaware that most beetles can fly, so having an image like this one of a blister beetle (Lytta auriculata) taking off is helpful in illustrating that beneath its wing covers a beetle has membranous wings it uses to fly.

Sometimes I can even capture courtship behavior, like between these two Golden Longwing butterflies, Heliconius hecale, native to Central America but performing locally in “Butterfly Magic” at the Tucson Botanical Gardens.

Here, the male is making hovering overtures to a female that is unreceptive. She signals this by essentially mooning him. Yeah, I used to get that a lot, too, dude….

Most of the time, I get images of insects arriving at, or departing from, a flower, or other perch. Here are a few examples:

Eumenes bollii potter waspVilla bee flyAmmophila thread-waisted wasp

Insects are the undisputed evolutionary pioneers of animal flight, so it should come as no surprise that they are masters of aerial maneuvering, speed (at least for their size), and durability. Even the butterflies banging their way around indoor butterfly exhibits are barely slowed down despite what one might consider devastating damage to their wings.

We stand to prosper by continuing research into insect flight. How can a dragonfly manufacture turbulence, something deadly to a fixed-winged aircraft, and then use that turbulence to generate lift? Imagine the possibilities if we could duplicate the intricacies of insect wing movements in our own planes and helicopters. Maybe we, ourselves, could ultimately float like a butterfly….

Sleepy Orange, Eurema nicippe