pharaohant's Identifications

On a cross-country trip to visit friends in Ohio, I stopped by this site in Adams County, Ohio, to see this Trachymyrmex septentrionalis population near the range limit of this species. I had learned about the exact location of this population from a septentrionalis worker-ant deposited in a museum collection, but the presence of septentrionalis in Adams County was already known and published in Wesson & Wesson 1940. The GPS coordinates posted here are for the center of Adams County, so not the exact location of this population, but the location is within 40 kilometer of the GPS coordinates indicated here.

The largest mounds of septentrionalis in this population seem larger than elswewhere where I have seen septentrionalis, and also the size of the topmost garden chamber (3rd photo) seems larger, 14 centimeter in horizontal diameter. I estimate that there are at least 300 septentrionalis colonies in this population in a total area of about a football field. Because this appears to be an isolated population at the range limit of this species, and probably only a handful of such populations exist in Ohio, we hope that this population remains protected.

T. septentrionalis is reported to occur also in Jackson County in Ohio (Ivanov 2019), and I explored some locations there that seemed to have sandy or sandy-clay soil, but I was unable to find septentrionalis during an afternoon of searching in Jackson County.

I also spent a day searching for T. septentrionalis in nearby West Virginia, because John Colburn Bridwell had collected septentrionalis on 11. June 1932 in Bancroft, Putnam County, West Virginia (I had seen Bridwell's collection deposited in a museum), but I was unable to find septentrionalis during a day of searching in north-western West Virginia.

The photos posted here are fuzzy, I apologize, because I did not notice that my camera was not set on macro.

observation UGM220628-01
elevation 194 meter