A century and a half after the first ant was recorded in Virginia, Dr. Kal Ivanov and colleagues have compiled the first comprehensive list of the ants in the Commonwealth.
The paper was published in February 2019 in the respected scientific journal “Zootaxa.” Ivanov, who is Assistant Curator of Invertebrate Zoology at the Virginia Museum of Natural History (VMNH), established the “Ants of Virginia Project” when he joined the museum in September 2014 and has been steadily working on the project for nearly five years.
“I was already aware that not much had been done on the ant fauna of the state, so it was just logical to begin by gathering all the available information on Virginia ants before moving forward,” Ivanov said. “2014 was spent reviewing the existing literature and compiling known records. Like any other study of this magnitude … one first wants to know what’s previously been done”.
After Dr. Shawn Dash of Virginia’s Hampton University joined the project, the next logical step was to look at any unpublished Virginia ant materials in existing collections, either by visiting museums or by examining digitized records available in online databases.
“Logically,” Ivanov said, “our starting point was the ant collection at the Virginia Museum of Natural History, which at the time contained only 907 ant specimens, many of them unidentified.”
The team then went on to examine collections at Virginia Tech, Radford University, the National Museum of Natural History and other institutions.
The project started with a working list of 130 different ant species previously reported from the state. In early 2015, Ivanov said, the team began fieldwork in different parts of Virginia in an attempt to sample as many of the state’s unique habitats as possible.
As a result of that fieldwork, the team added to the list another 34 ant species never before recorded in Virginia.
It is a testament, Ivanov said, to how little we know about the diversity of ants in Virginia.
How many ants are in Virginia?
The newly-published paper includes 164 different species and morphospecies (species that have yet to be formally described) of ants.
For the purposes of their paper, Ivanov and colleagues combined Virginia’s 95 counties and 38 independent cities into 103 “administrative units.” To date, the team has sampled for ants in approximately two-thirds of those units, he said, and they are planning to expand their coverage in the future.
In doing so, Ivanov said, there is little doubt that more ant species will be found in Virginia, including species that are currently unknown to science.
A 2012 study of the ants of North Carolina listed 192 species, Ivanov said, and given Virginia’s proximity and similarities to North Carolina, he expects Virginia harbors a similar number of ant species.
There are certain ant species, Ivanov said, that the team has yet to collect in the field even though they appear in scientific publications from the past. However, he said, it is hard to say if that means the species no longer occur in Virginia.
“That’s always the problem, not just with ants but with invertebrates in general,” Ivanov said. “If a grey wolf was recorded in Virginia back in the 1800s, and you can’t find it now, you know it’s gone. It’s hard to hide a wolf. With ants, especially rare species, we cannot be sure. Does it mean they’re gone? I don’t know. It may just mean we didn’t manage to collect them.”
When one considers the size of many ant species, it becomes clear how difficult they would be to find in the wild. With 20 recorded species, the small secretive ants in the genus Strumigenys represent the most diverse ant group in the Commonwealth. That doesn’t mean they are easy to find, however; due to their speck-like size and excellent camouflage, they are frequently overlooked during field work.
No matter what you’re collecting, Ivanov said, the unusual finds are always the most exciting.
“Be it a collection of stamps or PEZ dispensers or ants, you’re always looking for the rare thing, the thing that, for whatever reason, seems to elude you,” he said.
One example is Strumigenys memorialis, a tiny species of ant that, until recently, was known only from materials collected by Mark and Stephen Deyrup in Kentucky’s Daniel Boone National Forest. However, Ivanov said, when VMNH Executive Director Dr. Joe Keiper collected a leaf litter sample while in Chesapeake, Va. in 2016, Ivanov found within it a single specimen of this rare species.
“We’re talking about quite the range extension from eastern Kentucky all the way to the Coastal Plain of Virginia,” Ivanov said. “Does this species occur in between? By all means. But some species just don’t occur in large numbers, so you rarely if ever encounter them.”
Another exciting find occurred right in front of the Virginia Museum of Natural History. While on his lunch break, Ivanov spotted a winged queen ant on the sidewalk. Immediately recognizing it as something unusual, Ivanov collected it and took it to the lab.
The ant turned out to be Colobopsis obliqua, a square-headed ant that, like all ants in the genus Colobopsis, spends its life in the tree canopy. Ivanov had found the first – and to date, only – record of C. obliqua in Virginia.
There is no question, Ivanov said, that there are more ant species just waiting to be discovered in Virginia. He offered up the example of Mary Talbot, an entomologist who spent 30 years studying ants in the Edwin S. George Reserve in Livingston County, Michigan. Nearly every year, Ivanov said, Talbot would find an ant species she had never before spotted in the area. After 30 years of regular sampling at the two-square-mile reserve, she had recorded about two-thirds of all ant species known within the state of Michigan.
“Ultimately, with time, we’ll hit a plateau when we’re getting close to encountering all the taxa we expect,” Ivanov said. “We’re not expecting Virginia’s list to grow to 300 species. That’s never going to happen. But where exactly the cutoff is, we really don’t yet know.”
A work in progress
Ivanov’s chief area of interest is Hymenoptera, the order of insects that includes wasps, bees, sawflies and – of course – ants. Initiating a survey of the ants of Virginia was a logical choice, he said, especially since it had never been done before.
“That was rather unusual,” Ivanov said. “Ants are typically one of the groups that are targeted first, and that’s probably the result of a number of factors … their relative ease of collecting, high abundance, and ecological importance.”
In Virginia, he said, there have been a number of studies that have looked at ant diversity on a regional basis, be it in the Appalachian Mountains or the Coastal Plain. These were either limited surveys of a particular habitat or a particular park or preserve, or part of larger ecological studies. However, no one had assembled that information and put it all together.
Now that Ivanov and his team have taken the initiative and assembled that information, they hope it can provide a useful tool for researchers in the field.
“I’ve talked to many people that are interested in studying ants or using ants as tools for monitoring change, be it change caused by humans or natural changes,” Ivanov said. “If you don’t know what’s around, how do you proceed with such studies? It’s giving other researchers something to work with.”
Ivanov described the paper as a “celebration” of 150 years of Virginia ant research since Samuel Buckley first described three ant species from the state in 1867.
“It certainly is not the final word,” he said. “This is a work in progress. We compiled everything that is known, laid a solid base, and we added whatever new taxa we encountered along the way.”
Over time, Ivanov said, the team hopes to continue expanding the list as they find additional ant taxa in Virginia. Ivanov also hopes to eventually collaborate with other researchers and delve deeper into the lives and habits of these fascinating creatures.
“Natural history museums are one of few places where you still have the freedom to pursue such research,” he said. “I’m very lucky to be here.”