Leptostomia begaaensi: Small Pterosaur from Mid-Cretaceous Period Had Adaptations for Sediment Probing
Paleontologists in Morocco have discovered the fossilized remains that belonged to a unique small, long-beaked pterosaur.
The new pterosaur species, named Leptostomia begaaensis, lived between 113 and 94 million years ago (mid-Cretaceous period).
The flying reptile had a very long flattened toothless beak, and was similar in size to a turkey.
It likely used its beak to probe dirt and mud for hidden prey.
“The diets and hunting strategies of pterosaurs were diverse — they likely ate meat, fish and insects. The giant pterosaurs probably ate whatever they wanted,” said co-author Professor David Martill, a paleontologist at the University of Portsmouth.
“Some species hunted food on the wing, others stalked their prey on the ground. Now, the fragments of this remarkable little pterosaur show a lifestyle previously unknown for pterosaurs.”
“Leptostomia begaaensis may actually have been a fairly common pterosaur, but it’s so strange — people have probably been finding bits of this beast for years, but we didn’t know what they were until now,” said senior author Dr. Nick Longrich, a paleontologist in the Milner Centre for Evolution at the University of Bath.
The upper and lower jaws of Leptostomia begaaensis were recovered from the Cretaceous-period layers of the Kem Kem Basin in Morocco, North Africa.
Professor Martill, Dr. Longrich and their colleagues used CT scans to reveal an incredible network of internal canals for nerves that helped detect the prey underground.
“We’ve never seen anything like this little pterosaur before,” Professor Martill said.
“The bizarre shape of the beak was so unique, at first the fossils weren’t recognized as a pterosaur.”
The morphology of Leptostomia begaaensis’ beak most closely resembles that of probing birds such as kiwis, ibises, and curlews that probe in mud or earth for invertebrates.
The pterosaur could probably have done either, but its presence in the Kem Kem Formation — representing a rich ecosystem of rivers and estuaries — suggests it was drawn there to feed on aquatic prey.
“You might think of the pterosaur as imitating the strategy used successfully by modern birds, but it was the pterosaur that got there first,” Dr. Longrich said.
“Birds just reinvented what pterosaurs had already done tens of millions of years earlier.”
The team’s paper was published in the journal Cretaceous Research.
Roy E. Smith et al. 2021. A long-billed, possible probe-feeding pterosaur (Pterodactyloidea: ?Azhdarchoidea) from the mid-Cretaceous of Morocco, North Africa. Cretaceous Research 118: 104643; doi: 10.1016/j.cretres.2020.104643