Early Cretaceous Pterosaur Research Articles

Early Cretaceous pterosaur guano deposit from central Oregon, USA

Early Cretaceous pterosaur guano deposit from central Oregon, USA

First record of Early Cretaceous pterosaur from the Ordos Region, Inner Mongolia, China

ABSTRACT A new dsungaripterid pterosaur, Ordosipterus planignathus gen. et sp. nov., is established on the incomplete articulated lower jaws from the Lower Cretaceous Luohandong Formation in Otog Qi, Ordos Region, Inner Mongolia, China. It differs from other dsungaripterids mainly by having broad and low dentary at and just behind the mandibular symphysis, flat dentary dorsal plane forming the distinct lateral ridge with the curved dentary lateral side, and lower alveoli arranged along the dentary dorsolateral margin with wide spacing that increases from rostral to caudal. It represents the first diagnostic pterosaur from the Ordos Region in Inner Mongolia, and further enlarges the geographical distribution of the family Dsungaripteridae from northwestern China (together with western Mongolia) to central North China.

An Early Cretaceous pterosaur with an unusual mandibular crest from China and a potential novel feeding strategy.

The Aptian Jiufotang Formation of northeast China is a Konservat Lagerstätte particularly rich in pterosaurs, notably azhdarchoids. Here we describe a new genus and species of toothed pteranodontoid pterosaur, Ikrandraco avatar gen. et sp. nov., based on two laterally flattened specimens. Ikrandraco avatar is diagnosed by a suite of features, including a very low and elongate skull, strongly inclined quadrate, and a deep, blade-like bony mandibular crest with a hook-like process on its posterior edge, an unusual structure so far unique to this taxon. The particular skull shape hints at a distinct feeding habit for pterosaurs that potentially includes temporary skimming and an extensible skin acting as a throat pouch that was more developed than in any other pterosaur known so far. The presence of two other taxa of purported piscivorous pterosaurs in the Jiufotang Formation suggests distinct resource exploitation in this part of China during the Early Cretaceous.

An unusual edentulous pterosaur from the Early Cretaceous Romualdo Formation of Brazil

Numerous taxa make up the Early Cretaceous fauna of Brazil, including Ornithocheiroidea, Tapejaridae, Thalassodromidae, Chaoyangopteridae and a purported member of Azhdarchidae. Dsungaripteridae has only been tentatively assumed to be present in the form of ‘Santanadactylus’ spixi. New study of NMSG SAO 251093 (a specimen referred to Thalassodromeus sethi) suggests it is a previously unknown species of dsungaripterid, Banguela oberlii, tax. nov., differing from Thalassodromeus and other pterosaurs from the Early Cretaceous of Brazil by a unique combination of characters, including an upturned jaw tip, a short dorsal mandibular symphyseal shelf (dmss), and an autapomorphic thin crest placed halfway along the fused mandibular symphysis without a keel along the ventral margin of the jaw. B. oberlii, tax. nov., is referred to Dsungaripteridae based on a dmss no longer than the ventral shelf, U-shaped caudal margin of the ventral shelf and lateral margins of the mandibular symphysis concave in dorsal view. B. oberlii, tax. nov., is the youngest known dsungaripterid, and expands known morphological diversity in the clade as well as the Early Cretaceous pterosaur fauna of South America.

A functional odontoid in the dentary of the Early Cretaceous pterosaur Istiodactylus latidens: Implications for feeding

The Early Cretaceous ornithocheiroid pterosaur Istiodactylus latidens (Pterosauria, Archosauria, Reptilia) from the Wealden Supergroup of the Isle of Wight, southern England, has a distinctive dentition of labio-lingually compressed, sub-triangular tooth crowns with a triangular osseous projection at the dentary symphysis that occluded into a similarly shaped diastema between the first teeth of the left and right premaxillae and functioned as an odontoid (pseudotooth). A somewhat similar triangular bony projection occurs also in the istiodactylid Longchengpterus zhaoi from the Cretaceous of China. The possession of an odontoid at the dentary symphysis may be autapomorphy for Istiodactylidae. The apparent lack of an odontoid in other istiodactylids (Liaoxipterus brachyognathus Dong and Lü, 2005 and Istiodactylus sinensis Andres and Ji, 2006) may be a consequence of poor preservation.

New toothed flying reptile from Asia: close similarities between early Cretaceous pterosaur faunas from China and Brazil

Despite the great increase in pterosaur diversity in the last decades, particularly due to discoveries made in western Liaoning (China), very little is known regarding pterosaur biogeography. Here, we present the description of a new pterosaur from the Jiufotang Formation that adds significantly to our knowledge of pterosaur distribution and enhances the diversity of cranial anatomy found in those volant creatures. Guidraco venator gen. et sp. nov. has an unusual upward-directed frontal crest and large rostral teeth, some of which surpass the margins of the skull and lower jaw when occluded. The new species is closely related to a rare taxon from the Brazilian Crato Formation, posing an interesting paleobiogeographic problem and supporting the hypothesis that at least some early Cretaceous pterosaur clades, such as the Tapejaridae and the Anhangueridae, might have originated in Asia. The association of the new specimen with coprolites and the cranial morphology suggest that G. venator preyed on fish.

Early Cretaceous pterosaur tracks from a “buried” dinosaur tracksite in Shandong Province, China

Here we describe the pterosaur and tridactyl dinosaur footprint assemblage from a new tracksite in the Early Cretaceous Qugezhuang Formation near the Wenxiyuan Community in Jimo County-level City, Qingdao City, Shandong Province, East China. The construction of a community building has, since the discovery, covered the majority of tracks, but a few specimens on abandoned building stones constitute the first pterosaur track record in eastern China. The pterosaur tracks are assigned to Pteraichnus isp. and were probably made by a small to medium-sized pterodactyloid. The new pterosaur trackway contributes to the growing database of pterosaurian ichnites in Asia. The Wenxiyuan tridactyl dinosaur tracks are morphologically similar to those of theropods, but they are too poorly preserved to be referred to any particular ichnotaxon.

On the osteology of Tapejara wellnhoferi KELLNER 1989 and the first occurrence of a multiple specimen assemblage from the Santana Formation, Araripe Basin, NE-Brazil

The postcranial elements of two similar sized and juvenile individuals, along with a partial skull, are attributed to the Early Cretaceous pterosaur Tapejara wellnhoferi. The remains, recovered from a single concretion of the Romualdo Member, Santana Formation, NE-Brazil, represent the first account of multiple specimens having settled together and allow for a complete review of postcranial osteology in tapejarid pterosaurs. A comparison of long bone morphometrics indicates that all specimens attributed to the Tapejaridae for which these elements are known (i.e. Huaxiapterus, Sinopterus, Tapejara) display similar bivariate ratios, suggesting that Chinese and Brazilian taxa must have exhibited similar growth patterns. An unusual pneumatic configuration, whereby the humerus is pierced by both dorsally and ventrally located foramina, is observed within T. wellnhoferi, while the pneumatic system is inferred to have invaded the hindlimbs via the femur in all members of the Azhdarchoidea. The partial preservation of the endocranial cavity allows for a reconstruction of the tapejarid brain, where despite a small orbit with respect to skull size, the presence of large flocculi and ocular lobes indicate that Tapejara possessed both excellent balancing and visual systems as a consequence of its aerial lifestyle.

New pterosaur fossils from the Early Cretaceous (Albian) of Queensland, Australia

ABSTRACT Pterosaur fossils from Australia are rare. All the specimens that have been described previously are Cretaceous in age, with the majority deriving from the Aptian–Albian shallow marine succession within the Eromanga Basin of western Queensland. The Queensland specimens have tentatively been referred to the pterodactyloid clades Pteranodontidae, Ornithocheiridae, and Archaeopterodactyloidea (cf. Ctenochasmatoidea), each in varying taxonomic guises. Due to their fragmentary nature, more specific referrals of these specimens have not been possible. As such, the overall composition and more precise relationships of Australia's Cretaceous pterosaur fauna have remained enigmatic. Since 1987, a number of new pterosaur specimens have been found in the shallow marine late Albian rocks of the Eromanga Basin of western Queensland. Four of these specimens are described herein: a partial mandible, a metacarpal IV, a wing phalanx, and a humerus. The mandible is assigned to Ornithocheiridae, gen. et sp. indet., whereas the metacarpal and wing phalanx are assigned Ornithocheiridae cf. Anhanguera. The morphology of the humerus suggests that it may belong to a ctenochasmatoid lophocratian. Based on these findings, we hypothesize that Australia's Early Cretaceous pterosaur fauna comprises a mix of taxa already known to occur in Europe and South America in addition to a slightly younger ctenochasmatoid. However, the older specimens may alternatively represent new taxa that combine cranial characteristics of an Ornithocheirus-like taxon or a closely related form, with an Anhanguera-like postcranium. A more precise characterization of Australia's Cretaceous pterosaur fauna cannot be resolved until more complete specimens are found.

On the systematic relationships of Cearadactylus atrox, an enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil

Cearadactylus atrox, a large pterodactyloid pterosaur represented by an incomplete skull and lower jaw from the Lower Cretaceous Santana Formation of Brazil, is a valid species. Diagnostic characters include a mandibular symphysis with a transversely expanded "spatulate" anterior end that is considerably wider than the rostral spatula, and a third rostral tooth that has a basal diameter more than three times that of the fifth tooth. Additional diagnostic characters, contingent upon assignment of Cearadactylus atrox to the Ctenochasmatidae, include: anterior ends of jaws divaricate and containing 7 pairs of rostral teeth and 6 pairs of mandibular teeth; marked dimorphodonty, with an abrupt change in tooth morphology; and a "high check". "Cearadactylus? ligabuei" Dalla Vecchia, 1993, based on an incomplete skull, also from the Santana Formation, is not related to Cearadactylus atrox, exhibits several ornithocheirid synapomorphies and is referred, tentatively, to Anhanguera. Cearadactylus atrox exhibits various synapomorphies of the Ctenochasmatidae (rostrum anterior to nasoantorbital fenestra greater than half total skull length, teeth in anterior part of dentition relatively elongate and pencil-shaped, premaxilla has at least 7 pairs of teeth), the defining synapomorphy of the Gnathosaurinae (rostrum with dorsoventrally compressed laterally expanded spatulate anterior expansion), and shares two synapomorphies with the Chinese gnathosaurine Huanhepterus quingyangensis (anterior tips of jaws divaricate, teeth restricted to anterior half of mandible). Two elongate cervical vertebrae, also from the Santana Formation and previously assigned to "Santanadactylus brasilensis", are tentatively referred to Cearadactylus. Reconstruction of the temporal history of the Ctenochasmatidae suggests that while ctenochasmatines became increasingly specialised for filter feeding, gnathosaurines changed from sieve feeding to piscivory, acquiring several cranial characters that are similar to those of ornithocheirids, a group that also includes large aerial piscivores that used a terminal tooth grab for prey capture. Cearadactylus atrox aus der Santana-Formation (Unterkreide, NO-Brasilien) ist eine valide Art. Eine Revision des Taxons, von dem ein unvollständiger Schädel mit Unterkiefer vorliegt, ergab folgende diagnostische (autapomorphe) Merkmale. Die Symphyse hat ein transversal verbreitertes spatelförmiges Vorderende, das deutlich breiter ist als das Schnauzenende. Der dritte rostrale Zahn erreicht einen basalen Durchmesser, der jenen des fünften Zahns um das Dreifache übertrifft. Hinzu kommen Merkmale, die C. atrox mit der Ctenochasmatidae gemein hat, darunter die vorn auseinanderklaffenden Kieferränder, sieben rostrale Zahnpaare, sechs Unterkieferzahnpaare, eine ausgeprägte Dimorphodontie sowie eine hohe Wangenregion. "Cearadactylus ? ligabuei" Dalla Vecchia 1993, ebenfalls mit einem unvollständigen Schädel belegt, ist nicht näher mit C. atrox verwandt. Im Gegensatz zu letzterem zeigt "C. ? ligabuei" signifikante Ähnlichkeiten mit den Ornithocheiridae. Unter Vorbehalt wird er hier der Gattung Anhanguera zugeordnet. C. atrox hat neben eindeutigen Synapomorphien der Ctenochasmatidae, z. B. erreicht das Rostrum anterior des nasoantorbitalen Fensters mehr als die halbe Schädellänge, die vordersten Zähne sind verlängert und stiftförmig und die das Prämaxillare trägt mindestens sieben Zahnpaare. Daneben besitzt C. atrox auch noch die entscheidende Synapomorphie der Gnathosaurinae, nämlich ein Rostrum mit dorsoventral komprimierter vorderem Auswuchs. Außerdem ist C. atrox gekennzeichnet durch zwei Autapomorphien des Gnathosaurinen Huanhepterus quingyangensis aus China: divergierende Schnauzenenden und Zähne begrenzt auf vordere Kieferhälfte. Schließlich werden zwei lange Halswirbel, die auch aus der Santana Formation stammen und bislang zu Santanadactylus brasiliensis gerechnet wurden, unter Vorbehalt zu Cearadactylus gestellt. Die Evolutionsgeschichte der Ctenochasmatidae ist durch eine zunehmende Spezialisierung auf filternde Ernährungsweise gekennzeichnet. Die Gnathosaurinen dagegen stellten sich von der filternden auf eine piscivore Ernährung um, wobei sie eine Reihe von Schädelmerkmalen erworben haben, die den Ornithocheiriden konvergent ähnlich ist. doi:10.1002/mmng.20020050114

Pterosaur assemblages of the Jehol Biota and their implication for the Early Cretaceous pterosaur radiation

AbstractThe Early Cretaceous Jehol Biota from northeast China is well known for many beautifully preserved feathered dinosaurs, early birds and angiosperms. A great number of pterosaurs have also been discovered from the same deposits in recent years, representing arguably the best pterosaur assemblage from the Lower Cretaceous. Two pterosaur assemblages are recognized from the Jehol Biota, and represent two major adaptive radiations in the Early Cretaceous. The first radiation was preserved mainly in the Yixian Formation, and shows a strong resemblance to the Upper Jurassic pterosaur radiation in the Solnhofen Limestone of Germany. The second radiation was preserved in the Jiufotang Formation, with many of its taxa much similar to those of the pterosaur assemblages from the Lower Cretaceous Santana Formation of Brazil. Recent biostratigraphic work and radiometric datings of the Yixian and Jiufotang formations have provided a reliable geochronologic framework for the Jehol pterosaur radiations. The two major radiations occurred at about 125 Ma and 120 Ma, respectively. The radiations of the Jehol pterosaurs are characterized by a remarkable taxonomic diversity, great variation in body size, significant dietary differentiation, and occupancy of diverse niches. The appearance of several biological novelties was also critical in the success of the Jehol pterosaur radiations. The adaptive radiation of the Jehol pterosaurs was obviously coupled with the competition or co‐evolution with many other groups of the Jehol Biota. Among the flying animals in the Jehol Biota, pterosaurs were the major competitors for niches and food with birds. Although the Jehol pterosaurs probably fed mainly on fishes, the co‐evolution between plants and pterosaurs in the Jehol Biota might also have played a significant role in the pterosaur radiations, as is the case for plants and insects, birds, mammals and dinosaurs. Copyright © 2006 John Wiley & Sons, Ltd.

Pterosaurs as part of a spinosaur diet.

A remarkable specimen has been discovered of an Early Cretaceous pterosaur that has a tooth embedded in one of its cervical vertebrae: the tooth has been identified as one from a spinosaurid theropod dinosaur. This fossil is direct evidence that spinosaurs included items other than fish in their diet.

On the systematic relationships ofCearadactylus atrox, an enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil

On the systematic relationships ofCearadactylus atrox, an enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil

On the systematic relationships of <i>Cearadactylus atrox</i>, an enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil

<i>Cearadactylus atrox</i>, a large pterodactyloid pterosaur represented by an incomplete skull and lower jaw from the Lower Cretaceous Santana Formation of Brazil, is a valid species. Diagnostic characters include a mandibular symphysis with a transversely expanded "spatulate" anterior end that is considerably wider than the rostral spatula, and a third rostral tooth that has a basal diameter more than three times that of the fifth tooth. Additional diagnostic characters, contingent upon assignment of <i>Cearadactylus atrox</i> to the Ctenochasmatidae, include: anterior ends of jaws divaricate and containing 7 pairs of rostral teeth and 6 pairs of mandibular teeth; marked dimorphodonty, with an abrupt change in tooth morphology; and a "high check". "<i>Cearadactylus? ligabuei</i>" Dalla Vecchia, 1993, based on an incomplete skull, also from the Santana Formation, is not related to <i>Cearadactylus atrox</i>, exhibits several ornithocheirid synapomorphies and is referred, tentatively, to <i>Anhanguera. Cearadactylus atrox</i> exhibits various synapomorphies of the Ctenochasmatidae (rostrum anterior to nasoantorbital fenestra greater than half total skull length, teeth in anterior part of dentition relatively elongate and pencil-shaped, premaxilla has at least 7 pairs of teeth), the defining synapomorphy of the Gnathosaurinae (rostrum with dorsoventrally compressed laterally expanded spatulate anterior expansion), and shares two synapomorphies with the Chinese gnathosaurine <i>Huanhepterus quingyangensis</i> (anterior tips of jaws divaricate, teeth restricted to anterior half of mandible). Two elongate cervical vertebrae, also from the Santana Formation and previously assigned to "<i>Santanadactylus brasilensis</i>", are tentatively referred to <i>Cearadactylus</i>. Reconstruction of the temporal history of the Ctenochasmatidae suggests that while ctenochasmatines became increasingly specialised for filter feeding, gnathosaurines changed from sieve feeding to piscivory, acquiring several cranial characters that are similar to those of ornithocheirids, a group that also includes large aerial piscivores that used a terminal tooth grab for prey capture. <br><br> Cearadactylus atrox aus der Santana-Formation (Unterkreide, NO-Brasilien) ist eine valide Art. Eine Revision des Taxons, von dem ein unvollständiger Schädel mit Unterkiefer vorliegt, ergab folgende diagnostische (autapomorphe) Merkmale. Die Symphyse hat ein transversal verbreitertes spatelförmiges Vorderende, das deutlich breiter ist als das Schnauzenende. Der dritte rostrale Zahn erreicht einen basalen Durchmesser, der jenen des fünften Zahns um das Dreifache übertrifft. Hinzu kommen Merkmale, die <i>C. atrox</i> mit der Ctenochasmatidae gemein hat, darunter die vorn auseinanderklaffenden Kieferränder, sieben rostrale Zahnpaare, sechs Unterkieferzahnpaare, eine ausgeprägte Dimorphodontie sowie eine hohe Wangenregion. "<i>Cearadactylus ? ligabuei</i>" Dalla Vecchia 1993, ebenfalls mit einem unvollständigen Schädel belegt, ist nicht näher mit <i>C. atrox</i> verwandt. Im Gegensatz zu letzterem zeigt "<i>C. ? ligabuei</i>" signifikante Ähnlichkeiten mit den Ornithocheiridae. Unter Vorbehalt wird er hier der Gattung <i>Anhanguera</i> zugeordnet. <i>C. atrox</i> hat neben eindeutigen Synapomorphien der Ctenochasmatidae, z. B. erreicht das Rostrum anterior des nasoantorbitalen Fensters mehr als die halbe Schädellänge, die vordersten Zähne sind verlängert und stiftförmig und die das Prämaxillare trägt mindestens sieben Zahnpaare. Daneben besitzt <i>C. atrox</i> auch noch die entscheidende Synapomorphie der Gnathosaurinae, nämlich ein Rostrum mit dorsoventral komprimierter vorderem Auswuchs. Außerdem ist <i>C. atrox</i> gekennzeichnet durch zwei Autapomorphien des Gnathosaurinen <i>Huanhepterus quingyangensis</i> aus China: divergierende Schnauzenenden und Zähne begrenzt auf vordere Kieferhälfte. Schließlich werden zwei lange Halswirbel, die auch aus der Santana Formation stammen und bislang zu <i>Santanadactylus brasiliensis</i> gerechnet wurden, unter Vorbehalt zu <i>Cearadactylus</i> gestellt. Die Evolutionsgeschichte der Ctenochasmatidae ist durch eine zunehmende Spezialisierung auf filternde Ernährungsweise gekennzeichnet. Die Gnathosaurinen dagegen stellten sich von der filternden auf eine piscivore Ernährung um, wobei sie eine Reihe von Schädelmerkmalen erworben haben, die den Ornithocheiriden konvergent ähnlich ist. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20020050114" target="_blank">10.1002/mmng.20020050114</a>