18K; A Large Tegu-Like Lizard.
Middle Miocene, Climate Optimum,
Decatur County, GA
By
Thomas Thurman
02/March/2026
A large Tegu-like lizard hunted Decatur County in Southwest Georgia about 14.4 million years ago. In 2025 Jason R. Bourque and Edward L. Stanley announced a new genus and species of lizard known only from Decatur County, Georgia, Wautaugategu formidus. The fossil was a single thoracic vertebra. Their research appeared in the prestigious Journal of Paleontology. Their paper can be found at the base of this page.
Decatur County about 14.4 million years ago was a very different place. Sea levels were high and Florida was generally submerged with only an island chain, the Brooksville Ridge, above sea level. Decatur County was coastal and on the edge of the paleo Flint River, Chattahoochee River, and Spring Creek deltas. It isn’t impossible that the Paleo-Flint River met the sea very near where Gragg Mine stood.
Today, the confluence of these waterways is dammed at the Florida line by the Woodruff Dam. But if you look today at Google Earth and check the elevations around Gragg Mine you’ll see that it’s on modestly higher ground today that most of the surrounding area. Was this true during the Miocene? That’s hard to say, but it does suggest that this area could have been an island during high stands of sea levels.
Strange Gomphotherium elephants walked the county, they had two short tusks pointing down from the lower jaw and two larger tusks in the upper jaw, also pointing down with a rather short elephant trunk.
The large carnivore Amphicyon ingens or bear-dog was also present in numbers. A powerful, robust hunter whose shoulders were 1.25 meters (4+ feet) tall and whose dog-like head was as big as a man’s chest.
There were rhinoceroses, populations of early horses, populations of deer-like (Genus Paratoceras & family Dromomerycidae) animals whose antlers were fur covered, bony extensions of their skulls. Giant tortoises (Hesperotestudo), peccaries, wild dogs, members of the camel family, beavers, rabbits and many others. Decatur County was a very different place. Fossils from all of these were found within a few miles of Attapulgus.
Lists of recovered Miocene fossils can be found on this website on page #18J; Decatur County, Georgia’s Miocene Vertebrates In The Florida Museum of Natural History.
I want to thank Rachel Narducci, Lead Collections Manager of Vertebrate Paleontology at the Florida Museum of Natural History for forwarding this paper to me.
The Lizard
Wautaugategu formidus, is a member of the Tupinambinae (Teiidae family). Bourque and Stanley tell us that the Tupinambinae are group of medium to large bodied lizards native to South America which includes Tegu lizards which grow up to 1.3 meters (4 feet) long. The Tupinambinae are well represented in South America from the Eocene to the Pleistocene and believed to be more widespread in the Mesozoic to Paleogene. But this vertebra is the “oldest unequivocal record” in North America.
Wautaugategu formidus, is a member of the Tupinambinae (Teiidae family). Bourque and Stanley tell us that the Tupinambinae are group of medium to large bodied lizards native to South America which includes Tegu lizards which grow up to 1.3 meters (4 feet) long. The Tupinambinae are well represented in South America from the Eocene to the Pleistocene and believed to be more widespread in the Mesozoic to Paleogene. But this vertebra is the “oldest unequivocal record” in North America.
Etymology
To quote the authors: Combination of Wautauga in reference to the Wautauga State Forest, a local landmark near the type locality, and tegu, the colloquial name for T. teguixin and Salvator spp.”
“Wautauga State Forest” only comes up in a google search under the Climax, Georgia Chamber of Commerce. I see no listing for it in the Georgia Department of Natural Resources or U.S. Forest Service. Nor does it come up in Google Earth, though Google Earth produces two references on the name, one in West Virginia and one in Tennessee. Google Earth also shows a Wautauga Road running NE out of Attapulgus, Georgia but it’s over six miles from Climax at its closest point.
The fossil vertebra establishing Wautaugategu formidus was produced by Gragg Mine which is 3.5 miles SE of Attapulgus and more than 3 miles south of Wautauga Rd. So I’m not sure about the etimology of Wautauga
The specific name, formidus, is a Latin word meaning 'warm', alluding to the climatic conditions the taxon would have inhabited and the preferred body temperatures of living relatives.
To quote the authors: Combination of Wautauga in reference to the Wautauga State Forest, a local landmark near the type locality, and tegu, the colloquial name for T. teguixin and Salvator spp.”
“Wautauga State Forest” only comes up in a google search under the Climax, Georgia Chamber of Commerce. I see no listing for it in the Georgia Department of Natural Resources or U.S. Forest Service. Nor does it come up in Google Earth, though Google Earth produces two references on the name, one in West Virginia and one in Tennessee. Google Earth also shows a Wautauga Road running NE out of Attapulgus, Georgia but it’s over six miles from Climax at its closest point.
The fossil vertebra establishing Wautaugategu formidus was produced by Gragg Mine which is 3.5 miles SE of Attapulgus and more than 3 miles south of Wautauga Rd. So I’m not sure about the etimology of Wautauga
The specific name, formidus, is a Latin word meaning 'warm', alluding to the climatic conditions the taxon would have inhabited and the preferred body temperatures of living relatives.
Geologic Setting
Gragg Mine
The Wautaugategu formidus vertebra is Catalog# 546657 in the FLMNH database which can be accessed here; Web Portal. It came from the Gragg Mine, a now defunct fuller’s earth, clay mine. The fossil was collected in May 2005 by Jonathan Hoffman and Andrew Zimmerman. The Gragg Mine was located about 5.6 km southeast of Attapulgus but has since been reclaimed and reported from 2023 say the fossil beds are reforested, inaccessible, and likely buried during reclamation of the mine.
Gragg Mine
The Wautaugategu formidus vertebra is Catalog# 546657 in the FLMNH database which can be accessed here; Web Portal. It came from the Gragg Mine, a now defunct fuller’s earth, clay mine. The fossil was collected in May 2005 by Jonathan Hoffman and Andrew Zimmerman. The Gragg Mine was located about 5.6 km southeast of Attapulgus but has since been reclaimed and reported from 2023 say the fossil beds are reforested, inaccessible, and likely buried during reclamation of the mine.
The FLMNH database states the fossil came from the Torreya Formation, which is middle Miocene, but the paper does not state that.
Bourque and Stanley dated the sediments biochronologically, meaning by the presence of identified fossils whose range in geologic time is well known and established. Many fossils attributed to this, many mammals were recovered and identified and their fossils helped constrain the age of the deposit. Other fossils also played their part, particularly the presence of the rare, large-bodied salamander Batrachosauroides dissimulan (catalog# 217589) which exceeded three feet helped define the age of the sediments. Multiple specimens of this salamander genus were found in Gragg Mine and the Florida Museum holds other specimens of the same species from Florida and Texas, so the salamander could be confidently identified. Collectively the fossils established the age of the sediments as Middle Miocene, NALMA Barstovian 2, 14.8 to 14.0 million years old. (NALMA; North American Land Mammal Age)
Environment
The sediments represent a coastal fluvial deposit (Fluvial, river or stream sourced) with a mixture of marine, freshwater, and terrestrial vertebrates. That’s the paleo-environment. Gragg Mine is just south of the Flint River.
The sediments represent a coastal fluvial deposit (Fluvial, river or stream sourced) with a mixture of marine, freshwater, and terrestrial vertebrates. That’s the paleo-environment. Gragg Mine is just south of the Flint River.
These fossils are likely the remains of animals which got caught in ancient rivers, most likely the Paleo Flint River The Gragg Mine fossils included shark teeth, turtle material, snake material, lizards, Amphiuma, frogs, & others. “Marine and freshwater fish are the most abundant non-mammalian constituents.” (Bourque & Stanley) Another small-bodied teiid lizard was also present.
The Gragg Mine site is regionally important as it represents a coastal plain at the conclusion of one of the warmest periods of the Middle Miocene Climatic Optimum when sea levels were at their highest for the Neogene Period; 2.58 to 23.03 million years ago. As mentioned earlier, Florida was submerged except for the Brooksville Ridge in northern peninsular Florida as a series of islands and a scattering of barrier islands along the modern Georgia, Alabama border with Florida.
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Bourque & Stanley's Paper
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Reference:
- Bourque, Jason R. & Stanley, Edward L.; A Tegu-Like (Teiidae, Tupinambinae) from the Middle Miocene Climatic Optimum of the Southeastern United States. Journal of Paleontology, 99(1), pages 177-191, 2025