The discovery of a new type of extinct pterosaur belonging to the Tapejaridae Family (known primarily for their unusual bony crests on their skulls) has been announced. The fossils were uncovered in sandstone in a field near the municipality of Cruzeiro do Oeste in the state of Paraná in the Southern Region of Brazil in what some 80 to 85 mya (Late Cretaceous) had been an interdunal lake deposit (likely a desert oasis).
The researchers, headed by Paulo C. Manzig of the Paleontological Center (CENPÁLEO) at the Museum of Earth and Life at the University of Contestado in Brazil, report that a massive amount of fossilized material has been recovered from 20 square meter (215 sq. ft.) site representing a minimum of 47 individuals although the actual number present in this site must be well in the hundreds.
While none of the specimens are complete, in terms of the total assembly all elements of the skeleton are present. Most of the remains come from juveniles and since the fossils weren't crushed and flattened the three-dimension structure of the bones was preserved.
Finding such an intact fossil site is unusual. Although pterosaurs have been found on every continent, their fragile wing bones do not preserve well. Moreover, nearly all pterosaur remains have been found near what was once oceans or lagoons, and not in deserts.
The researchers named this previously unknown species and genus Caiuajara dobruskii with the generic name being a combination of the geologic formation, called the Caiuá Group, where it was found and Tapejarinae, the family it belongs in. The species name honors Alexandre Dobruski and his son João Gustavo Dobruski, two local farmers who actually found the site back in 1971.
The wingspans of the individuals ranged in size from between 65 cm (2.1') to 235 cm (7.7') in length. One of the co-authors, Alexander Kellner a paleontologist at the Federal University of Rio de Janeiro, noted that Caiuajara was precocial (meaning the young are relatively mature and mobile). Since the adult skeletal size (other than the head) wasn't much different from the juveniles', Caiuajara had the wingspan needed to take flight at a very young age.
As for the head, it had an enormous shark fin-shaped crest on the snout that has caused many observers to liken it to a butterfly wing. According to the researchers Caiuajara's bony crests changed in size and orientation as the pterosaurs grew. The crest appeared to change from small and inclined in juveniles, to large and steep in adults (up to 90°).
Caiuajara is to date the geologically youngest known tapejarid as well as being the most southern one known (it is also the first pterosaur of any kind found in southern Brazil).
Further, Manzig and his colleagues think that this expansion of their known range is an indication that tapejarids had a global distribution.
According to Kellner Caiuajara inhabited the area for quite some time rather than being temporary residents. "The presence of three main levels of accumulation in a section of less than one meter suggests that this region was home to pterosaur populations for an extended period of time."
As indicated, the multiple levels indicate that they didn't die all at once yet the cause of death remains unknown. The researchers did state that similarities with dinosaur drought-related mortality are striking but leave room for the possibility that sand storms might have been responsible.
Finally, the fact that so many were unearthed in a single bone bed is seen as the strongest evidence so far that pterosaurs were social animals, living a gregarious lifestyle in colonies. Earlier discovery of the filter-feeding Pterodaustro in Patagonia, Argentina that lived 105 mya and scattered pterosaur bones found in northern Chile provided the first evidence of pterosaurs living together in flocks
Further Reading:
Discovery of a Rare Pterosaur Bone Bed in a Cretaceous Desert with Insights on Ontogeny and Behavior of Flying Reptiles Abstract & Paper
New Flying Reptile Found in "Unprecedented" Pterosaur Boneyard
Caiuajara dobruskii: New Pterosaur Species Discovered in Brazil
New species of flying pterosaur: Bones from nearly 50 ancient flying reptiles discovered
'Butterfly-headed' flying reptiles were social say paleontologists
New Species of Flying Pterosaur Found in Brazilian 'Graveyard'
Fossils of 'Butterfly-Headed' Flying Reptiles Discovered in Brazil
Caiuajara Dobruskii: 47 Ancient Flying Reptiles Of New Species Discovered
Ancient Butterfly-Headed Flying Reptile Discovered
The researchers, headed by Paulo C. Manzig of the Paleontological Center (CENPÁLEO) at the Museum of Earth and Life at the University of Contestado in Brazil, report that a massive amount of fossilized material has been recovered from 20 square meter (215 sq. ft.) site representing a minimum of 47 individuals although the actual number present in this site must be well in the hundreds.
While none of the specimens are complete, in terms of the total assembly all elements of the skeleton are present. Most of the remains come from juveniles and since the fossils weren't crushed and flattened the three-dimension structure of the bones was preserved.
Finding such an intact fossil site is unusual. Although pterosaurs have been found on every continent, their fragile wing bones do not preserve well. Moreover, nearly all pterosaur remains have been found near what was once oceans or lagoons, and not in deserts.
The researchers named this previously unknown species and genus Caiuajara dobruskii with the generic name being a combination of the geologic formation, called the Caiuá Group, where it was found and Tapejarinae, the family it belongs in. The species name honors Alexandre Dobruski and his son João Gustavo Dobruski, two local farmers who actually found the site back in 1971.
The wingspans of the individuals ranged in size from between 65 cm (2.1') to 235 cm (7.7') in length. One of the co-authors, Alexander Kellner a paleontologist at the Federal University of Rio de Janeiro, noted that Caiuajara was precocial (meaning the young are relatively mature and mobile). Since the adult skeletal size (other than the head) wasn't much different from the juveniles', Caiuajara had the wingspan needed to take flight at a very young age.
As for the head, it had an enormous shark fin-shaped crest on the snout that has caused many observers to liken it to a butterfly wing. According to the researchers Caiuajara's bony crests changed in size and orientation as the pterosaurs grew. The crest appeared to change from small and inclined in juveniles, to large and steep in adults (up to 90°).
Caiuajara is to date the geologically youngest known tapejarid as well as being the most southern one known (it is also the first pterosaur of any kind found in southern Brazil).
Further, Manzig and his colleagues think that this expansion of their known range is an indication that tapejarids had a global distribution.
According to Kellner Caiuajara inhabited the area for quite some time rather than being temporary residents. "The presence of three main levels of accumulation in a section of less than one meter suggests that this region was home to pterosaur populations for an extended period of time."
As indicated, the multiple levels indicate that they didn't die all at once yet the cause of death remains unknown. The researchers did state that similarities with dinosaur drought-related mortality are striking but leave room for the possibility that sand storms might have been responsible.
Finally, the fact that so many were unearthed in a single bone bed is seen as the strongest evidence so far that pterosaurs were social animals, living a gregarious lifestyle in colonies. Earlier discovery of the filter-feeding Pterodaustro in Patagonia, Argentina that lived 105 mya and scattered pterosaur bones found in northern Chile provided the first evidence of pterosaurs living together in flocks
Caiuajara dobruskii3.jpg
artist reconstruction indicating what the crest was like
Caiuajara dobruskii1.jpg
Holotype on left with a paratype on right
Caiuajara dobruskii2.jpg
An indication of some of the material recovered
artist reconstruction indicating what the crest was like
Caiuajara dobruskii1.jpg
Holotype on left with a paratype on right
Caiuajara dobruskii2.jpg
An indication of some of the material recovered
Further Reading:
Discovery of a Rare Pterosaur Bone Bed in a Cretaceous Desert with Insights on Ontogeny and Behavior of Flying Reptiles Abstract & Paper
New Flying Reptile Found in "Unprecedented" Pterosaur Boneyard
Caiuajara dobruskii: New Pterosaur Species Discovered in Brazil
New species of flying pterosaur: Bones from nearly 50 ancient flying reptiles discovered
'Butterfly-headed' flying reptiles were social say paleontologists
New Species of Flying Pterosaur Found in Brazilian 'Graveyard'
Fossils of 'Butterfly-Headed' Flying Reptiles Discovered in Brazil
Caiuajara Dobruskii: 47 Ancient Flying Reptiles Of New Species Discovered
Ancient Butterfly-Headed Flying Reptile Discovered
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