Science journalist Tim Wall has covered the flying reptile research of SMU’s Timothy S. Myers on his popular Discovery News Online blog. Wall’s March 2 entry aptly warns “Don’t mess with Texas Pterosaurs!”
Myers identified fossilized bones discovered in Texas from a flying reptile that died 89 million years ago. The bones may be the world’s earliest occurrence of the prehistoric creature known as Pteranodon, Myers says.
Pteranodon was a type of pterosaur that lived about the same time as some dinosaurs, about 100 million to 65 million years ago. The only reptiles to dominate the ancient skies, pterosaurs had broad leathery wings and slim torsos.
The specimen identified by Myers had a wing span between 12 and 13 feet, or 3.6 to 4 meters. It was discovered in a rock unit that dates to early in the Late Cretaceous.
By Tim Wall
Discovery News Online
Don’t mess with Texas Pterosaurs! They are the oldest yet found in North America. One recently found specimen may even be the oldest Pteranodon in the world.
The mystery flying reptile a type of pterosaur, took a final plunge 89 million years ago into the waters of the inland sea that once covered the central United States. It sank to the bottom, fossilized, and lay there until amateur fossil hunter Gary Byrd found the ancient aviator’s bones. They were uncovered during the excavation of a culvert in a new subdivision north of Dallas.
Pterosaur Windsurfed Across Surface of Prehistoric Seas
“I found a couple parts of a fish, and then when I saw these my initial thought was that they weren’t fish,” Byrd, a roofing contractor by day, said in a Southern Methodist University press release. “I kind of knew it was something different — a birdlike thing. It’s very rare you find those thin, long bones.”
Byrd already has a species of duckbill dinosaur, Protohadros byrdi, named after him in 1994. He donated the fossils to Southern Methodist University’s Shuler Museum of Paleontology.
At the museum, Timothy Myers identified the bones as belonging to the left wing of a pterosaur, most likely a Pteranodon.
New Dino-Eating Pterosaur Evolved in Unusual Way
“If it wasn’t crushed so badly, it would be possible to determine if it really is Pteranodon,” Myers said in a SMU press release. “These bones are easily flattened. They are hollow inside, because they have to be lightweight to allow a pterosaur to fly. So they compress like a pancake as they’re embedded in layers of rock.”
Unique specimen is first of its kind discovered as far south as Texas, where it flew over a vast ancient sea
Fossilized bones discovered in Texas from a flying reptile that died 89 million years ago may be the earliest occurrence of the prehistoric creature known as Pteranodon.
Previously, Pteranodon bones have been found in Kansas, South Dakota and Wyoming in the Niobrara and Pierre geological formations. This likely Pteranodon specimen is the first of its kind found in Texas, according to paleontologist Timothy S. Myers at Southern Methodist University in Dallas, who identified the reptile. The specimen was discovered north of Dallas by an amateur fossil hunter who found various bones belonging to the left wing.
Pteranodon was a type of pterosaur that lived about the same time as some dinosaurs, about 100 million to 65 million years ago. The only reptiles to dominate the ancient skies, pterosaurs had broad leathery wings and slim torsos.
Adult pterosaur, toothless variety with about a 12-foot wing span
The specimen identified by Myers is an adult pterosaur of the toothless variety and while larger than most birds, wasn’t among the largest pterosaurs, Myers said, noting it had a wing span between 12 and 13 feet, or 3.6 to 4 meters. It was discovered in the Austin Group, a prominent rock unit in Texas that was deposited around 89 million years ago, early in the geological time period called the Late Cretaceous.
Pterosaurs, many of which survived on fish, lived at a time when a massive ancient sea cut across the central United States. The Western Interior Seaway was a shallow body of water that split North America in half from the Arctic Ocean to the Gulf of Mexico.
More than a thousand Pteranodon fossils have been unearthed from the middle part of the seaway.
No definitive Pteranodon specimens have emerged from the southern part that is now Texas.
The SMU specimen, if it is Pteranodon, would be the first discovered so far south in the Western Interior Seaway, said Myers, a postdoctoral researcher in SMU’s Huffington Department of Earth Sciences.
Left wing suggests Pteranodon; cause of death a mystery
Key to identifying the SMU fossils as Pteranodon is a humerus of 5.7 inches, or 14.5 centimeters. The humerus is the uppermost bone in the wing and attaches to the torso. The humerus of the SMU specimen, while complete, did suffer some damage during fossilization when it became compressed and distorted through millions of years of compaction.
Book a live interview
To book a live or taped interview with Timothy S. Myers in the SMU News Broadcast Studio call SMU News at 214-768-7650 or email news@smu.edu.
“If it wasn’t crushed so badly, it would be possible to determine if it really is Pteranodon,” Myers said. “These bones are easily flattened. They are hollow inside, because they have to be lightweight to allow a pterosaur to fly. So they compress like a pancake as they’re embedded in layers of rock.”
While it’s difficult to narrow the humerus definitively to a specific genus and species, some features clearly identify the specimen as part of the Pteranodontidae family, most likely the genus Pteranodon. It exhibits, for example, the prominent warped deltopectoral crest that is characteristic of members of the Pteranodontidae family, called pteranodontids, he said.
Discovered along with the humerus were parts of the elongated fourth finger that in pterosaurs forms the wing. The SMU specimen’s metacarpal — at 20 centimeters — is incomplete, missing an estimated 37 percent of its length.
The fossils do not solve the mystery of the reptile’s cause of death, Myers said. But it appears the animal probably died in flight over the sea and then fell into the water. Its carcass probably floated for some time, so that when the flesh decomposed the bones separated at the joints, known as “disarticulation,” before they settled to the sea floor and were buried.
“We know it was disarticulated when it was buried because the bones weren’t preserved in correct anatomical position,” Myers said. “Abrupt truncation of the broken end of one of the bones and infilling of the break with sediment also indicates that the breakage and disarticulation took place prior to burial.”
May be oldest Pteranodon in world
If the specimen represents Pteranodon, Myers said, it would be the oldest one in North America by 1 million to 2 million years, and the second oldest pteranodontid in the world.
Pterosaurs were alive from the Late Triassic — more than 200 million years ago — to the Late Cretaceous, evolving from small-bodied creatures to some of the largest animals to ever inhabit the skies, Myers said. An older pteranodontid specimen, belonging to the genus Ornithostoma, previously was identified in England.
“Any pterosaur material is fairly rare to find unless you have exceptional preservation conditions. They are frail, fragile bones, and they require rapid burial to be well preserved,” Myers said. “The SMU specimen was deposited relatively far offshore in deep water, perhaps 50 to 80 feet deep. It’s fairly exceptional because of the number of elements. Typically you’ll only find one piece, or one part of a piece in the local rock.”
During the Early Cretaceous, many types of pterosaurs lived around the world, Myers said. The earliest ones had thin, razor-sharp teeth. In the transition from Early to Late Cretaceous, the toothed variety disappear from the fossil record and toothless forms, like the SMU specimen, become more common, he said.
Dallas area specimens illustrate pterosaur evolution
North Texas is fortunate to have had both the toothed and toothless kinds discovered in the area, illustrating the evolutionary transition, noted Myers.
Besides the toothless specimen just identified by Myers, an older toothed pterosaur, Aetodactylus halli, previously was discovered in the Dallas area. Aetodactylus, also identified by Myers, lived 95 million years ago.
“This new specimen adds a lot more information about pterosaurs in North America,” Myers said. “It helps constrain the timing of the transition from toothed to toothless because there’s only a few million years separating this specimen and Aetodactylus.”
Amateur fossil collector Gary Byrd of Rockwall, Texas, discovered the new SMU pterosaur fossils about 10 years ago.
A roofing contractor who keeps an eye out for fossils, Byrd made the find after stopping to look at two freshly excavated culverts while driving through a new subdivision in Collin County. Using a hammer and pick he dug out the bones and brought them to SMU paleontologists Louis Jacobs and Dale Winkler. Jacobs and Winkler indicated the fossils were likely a pterosaur. Byrd donated the fossils to SMU’s Shuler Museum of Paleontology.
“I found a couple parts of a fish, and then when I saw these my initial thought was that they weren’t fish,” Byrd recalled. “I kind of knew it was something different — a birdlike thing. It’s very rare you find those thin, long bones.”
This isn’t the first time Byrd has hit it lucky finding fossils. In 1994 he discovered dinosaur bones that he donated to SMU’s Shuler Museum. The specimen was identified as a rare primitive duck-billed dinosaur and named Protohadros byrdi after Byrd. — Margaret Allen
National Geographic News interviewed SMU postdoctoral researcher Timothy S. Myers about the new species and genus of pterosaur he identified and named, Aetodactylus Halli.
In the April 28 article “Toothy Texas Pterosaur Found; Soared Over Dallas” reporter John Roach talked to Myers about the 95 million-year-old jaw that was discovered by Lake Worth resident Lance Hall.
The pterosaur flew over the ancient sea that used to cover much of the Dallas-Fort Worth area. A rare species of pterosaur in North America, Myers named the new flying reptile after Hall.
Others who wrote about Myers’ Aetodactylus Halli research include:
By John Roach
National Geographic News
Long before six flags flew over Texas, a newfound species of winged reptile
with an exceptionally toothy grin owned the skies over what is now the Lone
Star State.
The recently discovered pterosaur, dubbed Aetodactylus halli, was identified based on a 95-million-year-old lower jawbone found outside of Dallas by amateur fossil hunter Lance Hall.
The pterosaur had a relatively slender jaw filled with thin, needlelike teeth, which might have helped the creature pluck fish from the shallow sea that once covered the region, a new study says.
“It was hanging out near the ocean, and that is probably where it derived its food from,” said study leader Timothy Myers, a paleontologist at Southern Methodist University in Dallas.
By comparing the jawbone to more complete pterosaur fossils, Myers and his team think A. halli was a medium-size animal with a nine-foot (three-meter) wingspan and a short tail.
Texas’s Toothy Pterosaur a Rare Find
Pterosaurs ruled the skies from the late Triassic period, more than 200 million years ago, until dinosaurs went extinct at the end of the Cretaceous, about 65 million years ago.
A 95 million-year-old fossilized jaw discovered in Texas has been identified as a new genus and species of flying reptile, Aetodactylus halli.
Aetodactylus halli is a pterosaur, a group of flying reptiles commonly referred to as pterodactyls.
The rare pterosaur — literally winged lizard — is one of the youngest members in the world of the pterosaur family Ornithocheiridae, says paleontologist Timothy S. Myers, who identified and named Aetodactylus halli.
The newly identified reptile is only the second ornithocheirid ever documented in North America, Myers says. He is a postdoctoral fellow in the Roy M. Huffington Department of Earth Sciences at Southern Methodist University in Dallas.
Aetodactylus halli would have soared over what is now the Dallas-Fort Worth area during the Cretaceous Period when much of the Lone Star state was under water, covered by a vast ancient sea.
While rare in North America, toothed pterosaurs belonging to the Ornithocheiridae are a major component of Cretaceous pterosaur faunas elsewhere in the world, Myers says. The Texas specimen — a nearly complete mandible with most of its 54 teeth missing — is definitively younger than most other ornithocheirid specimens from Brazil, England and China, he says. It is five million years younger than the only other known North American ornithocheirid.
Myers named the pterosaur Aetodactylus halli after Lance Hall, a member of the Dallas Paleontological Society who hunts fossils for a hobby. Hall found the specimen in 2006 in North Texas. It was embedded in a soft, powdery shale exposed by excavation of a hillside next to a highway. The site was near the city of Mansfield, southwest of Dallas and west of Joe Pool Lake. Hall donated the specimen to SMU.
Pterosaurs ruled the skies from the late Triassic, more than 200 million years ago, to the end of the Cretaceous, about 65 million years ago, when they went extinct. They represent the earliest vertebrates capable of flying.
Fossil hunter saw long row of teeth sockets
The Aetodactylus halli jaw was discovered in the geologic unit known as the Eagle Ford Group, which comprises sediments deposited in a shallow sea, Myers says. Outcrop of the Eagle Ford Group extends northward from southwestern Texas into southern Oklahoma and southwestern Arkansas.
“I was scanning the exposure and noticed what at first I thought was a piece of oyster shell spanning across a small erosion valley,” Hall recalls of the discovery. “Only about an inch or two was exposed. I almost passed it up thinking it was oyster, but realized it was more tan-colored like bone. I started uncovering it and realized it was the jaw to something — but I had no idea what. It was upside down and when I turned over the snout portion it was nothing but a long row of teeth sockets, which was very exciting.”
SMU vertebrate paleontologist Louis L. Jacobs, a dinosaur expert internationally recognized for his fossil discoveries in Texas and Africa, and SMU paleontologist Michael J. Polcyn, recognized for his expertise on the extinct marine reptiles called mosasaurs, both told Hall it was a pterosaur and an important find.
Unique jaw differs from others
The 38.4-centimeter Aetodactylus jaw originally contained 54 slender, pointed teeth, but only two remain in their sockets, Myers says. The lower teeth were evenly spaced and extended far back along the jaw, covering nearly three quarters of the length of the mandible. The upper and lower teeth interlaced when the jaws were closed.
In Aetodactylus, changes in tooth size along the jaw follow a similar pattern to those of other ornithocheirids. However, Aetodactylus differs from all other ornithocheirids in that its jaws were thin and delicate, with a maximum thickness not much greater than 1 centimeter, Myers says. But the specimen does compare favorably with Boreopterus, a related pterosaur from the Early Cretaceous of China, in terms of the number of teeth present in the lower jaw, he says.
Myers has estimated the wingspan around roughly 3 meters, or about 9 feet, indicating Aetodactylus would have been a “medium-sized” pterosaur, he says. While it’s not known how Aetodactylus died, at the time of death the reptile was flying over the sea and fell into the water, perhaps while fishing, Jacobs says.
Find hints at new diversity of pterosaurs
North American pterosaurs that date from the Cretaceous are all toothless, except for Aetodactylus and Coloborhynchus, Myers says. The thinness of the jaws, upward angle of the back half of the mandible and the lack of a pronounced expansion of the jaw tips indicate that Aetodactylus is different from other ornithocheirids and represents a new genus and species of pterosaur.
“Discovery of another ornithocheirid species in Texas hints at a diversity of pterosaurs in the Cretaceous of North America that wasn’t previously realized,” Myers says. “Aetodactylus also represents one of the final occurrences of ornithocheirids prior to the Late Cretaceous transition to pterosaur faunas that were dominated by the edentulous, or toothless, species.”
Texas now claims the only two of their kind
Hall on April 14 was presented with the Dallas Paleontological Society’s highest honor, the Lloyd Hill award. The award is named for the late Lloyd Hill, an amateur fossil hunter and longtime member of the Dallas Paleontological Society. Hill wrote the well-regarded novel The Village of Bom Jesus.
Much of Texas was once submerged under the Western Interior Seaway. The massive sea split North America from the Gulf of Mexico to the Arctic Ocean.
On shore, the terrain was flat and flowering plants were already dominating flora communities in this part of North America, according to paleobotanist Bonnie Jacobs, associate professor of Earth Sciences at SMU.
“There were still conifers and ferns as well, but mostly of the sort that had tiny needle leaves, like junipers,” says Bonnie Jacobs. “Sycamores and their relatives would have been among the flowering plants.”
The first ornithocheirid remains from North America, discovered in Fort Worth, were described by former SMU student Young-Nam Lee and donated by amateur collector Chris Wadleigh, says SMU’s Louis Jacobs.
“The ancient sea that covered Dallas provided the right conditions to preserve marine reptiles and other denizens of the deep, as well as the delicate bones of flying reptiles that fell from their flight to the water below,” says Louis Jacobs, a professor in SMU’s Huffington Department of Earth Sciences.
“The rocks and fossils here record a time not well represented elsewhere in North America,” says Louis Jacobs. “That’s why two species of ornithocheirids have been found here but nowhere else, and that’s why discoveries of other new fossils are sure to be made by Lance Hall and other fossil lovers.”
Myers’ article in the Journal of Vertebrate Paleontology is titled “A new ornithocheirid pterosaur from the Upper Cretaceous (Cenomanian-Turonian) Eagle Ford Group of Texas.”
The Congo Basin — with its massive, lush tropical rain forest — was far different 150 million to 200 million years ago.
At that time Africa and South America were part of the single continent Gondwana. The Congo Basin was arid, with a small amount of seasonal rainfall, and few bushes or trees populated the landscape, according to a new geochemical analysis of rare ancient soils.
“There aren’t a whole lot of terrestrial deposits from that time period preserved in Central Africa,” Myers says. “Scientists have been looking at Africa’s paleoclimate for some time, but data from this time period is unique.”
There are several reasons for the scarcity of deposits: Ongoing armed conflict makes it difficult and challenging to retrieve them; and the thick vegetation, a humid climate and continual erosion prevent the preservation of ancient deposits, which would safeguard clues to Africa’s paleoclimate.
Myers’ research is based on a core sample drilled by a syndicate interested in the oil and mineral deposits in the Congo Basin. Myers accessed the sample — drilled from a depth of more than 2 kilometers — from the Royal Museum for Central Africa in Tervuren, Belgium, where it is housed. With the permission of the museum, he analyzed pieces of the core at the SMU Huffington Department of Earth Science’s Isotope Laboratory.
“I would love to look at an outcrop in the Congo,” Myers says, “but I was happy to be able to do this.”
The Samba borehole, as it’s known, was drilled near the center of the Congo Basin. The Congo Basin today is a closed canopy tropical forest — the world’s second largest after the Amazon. It’s home to elephants, great apes, many species of birds and mammals, as well as the Congo River.
Myers’ results are consistent with data from other low paleolatitude, continental, Upper Jurassic deposits in Africa, and with regional projections of paleoclimate generated by general circulation models, he says.
“It provides a good context for the vertebrate fossils found in Central Africa,” Myers says. “At times, any indications of the paleoclimate are listed as an afterthought, because climate is more abstract. But it’s important because it yields data about the ecological conditions. Climate determines the plant communities, and not just how many, but also the diversity of plants.”
While there was no evidence of terrestrial vertebrates in the deposits Myers studied, dinosaurs were present in Africa at the same time. Their fossils appear in places that were once closer to the coast and probably wetter and more hospitable, he says.
The Belgium samples yielded good evidence of the paleoclimate. Myers found minerals indicative of an extremely arid climate typical of a marshy, saline environment. With the Congo Basin at the center of Gondwana, humid marine air from the coasts would have lost much of its moisture content by the time it reached the interior of the massive continent.
“There probably wouldn’t have been a whole lot of trees; more scrubby kinds of plants,” Myers says.
The clay minerals that form in soils have an isotopic composition related to that of the local rainfall and shallow groundwater. The difference in isotopic composition between these waters and the clay minerals is a function of surface temperature, he says. By measuring the oxygen and hydrogen isotopic values of the clays in the soils, researchers can estimate the temperature at which the clays formed.
By artist Karen Carr / See 
