Photo from Simon Fraser University Public Affairs and Media Relations
According to Taylor
"This fossil comes from the American Green River Formation, in present-day Wyoming. At 51 mm in length, this is one of the largest known ants, rivalled in the modern fauna only by the marginally longer but possibly less robust driver ant Dorylus wilverthi "
According to Wiki
The fossil ant Titanomyrma lubei was discovered in ancient lake sediments in the DMNS locality 784, Farson Fish Beds, Laney Member of the Green River Formation; Sweetwater County, Wyoming, USA by Louis Lube, the collector and donor of the holotype specimen. The fossil formed part of the collection of Denver Museum of Nature and Science and was discovered by Bruce Archibald and co-author and museum chief curator Kirk R. Johnson while casually going through storage drawers. The fossil depicts the queen ant only and no fossils of workers have been found. With the discovery of Titanomyrma lubei and the description of the genus, two other species of giant ants, Formicium giganteum and Formicium simillimum, were reclassified into this genus.
Beautifully preserved fossils of Titanomyrma giganteum and Titanomyrma simillimum were discovered in the Messel shales, 30 km south of Frankfurt am Main, in Germany. A related undescribed species has been found in the nearby Eckfeld Maar.