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Pterosaurs, the first vertebrates to evolve active flight, lived between 210 and 66 million years ago. They were important components of Mesozoic ecosystems, and reconstructing pterosaur diets is vital for understanding their origins, their roles within Mesozoic food webs and the impact of other flying vertebrates (i.e. birds) on their evolution. However, pterosaur dietary hypotheses are poorly constrained as most rely on morphological-functional analogies. Here we constrain the diets of 17 pterosaur genera by applying dental microwear texture analysis to the three-dimensional sub-micrometre scale tooth textures that formed during food consumption. We reveal broad patterns of dietary diversity (e.g. Dimorphodon as a vertebrate consumer; Austriadactylus as a consumer of ‘hard’ invertebrates) and direct evidence of sympatric niche partitioning (Rhamphorhynchus as a piscivore; Pterodactylus as a generalist invertebrate consumer). We propose that the ancestral pterosaur diet was dominated by invertebrates and later pterosaurs evolved into piscivores and carnivores, shifts that might reflect ecological displacements due to pterosaur-bird competition., Microwear patterns on teeth can be used to infer diet as different foods leave different marks. Here, Bestwick and colleagues analyse microwear from the teeth of pterosaurs—extinct flying reptiles colloquially known as “pterodactyls”—to reconstruct their dietary diversity and evolution.

A new juvenile specimen ofPteranodonfrom the Smoky Hill Chalk Member of the Niobrara Formation of western Kansas had an estimated wingspan in life of 1.76 m, ~45% smaller than the smallest previously known specimens, but does not differ in morphology from larger specimens. Its presence indicates that juveniles were capable of flying long distances, so it falsifies the interpretation ofPteranodonas growing rapidly to adult size under parental care before flying. Instead juveniles were precocial, growing more slowly to adult size while flying and feeding independently for several years before going to sea. Because juveniles are otherwise unknown in the Smoky Hill Chalk Member, they must have occupied different environments and ecological niches than adults; thusPteranodonexhibited ontogenetic niches. Evidence is presented that most other pterosaurs (e.g.,Rhamphorhynchus,Pterodactylus,Anhanguera) also exhibited various ontogenetic niches, which, along with their large body size, suggests that pterosaur taxonomic diversity was rather low, like that of crocodilians.

The Zittel wing ofRhamphorhynchus muensteriis reinterpreted as preserving negative impressions of closely spaced broad flat actinofibrils that were replaced by calcite but were prepared away by the specimen’s finder. The Marsh specimen preserves positive impressions of the dorsal and ventral surfaces of the wing, which show that the skin was smooth with fine wrinkles and that actinofibrils were not on the wing surface. Based on comparisons of those specimens, the dactylopatagium consisted of dorsal and ventral skins of epidermis and dermis surrounding a common hypodermis core, and keratinous actinofibrils developed in place within the dorsal epidermis adjacent to a layer of linear collagen fibers in the dorsal dermis. The actinofibrils and linear collagen fibers together formed the main functional structure of the dactylopatagium. That structure made the dactylopatagium somewhat stiff and essentially inextensible so that it folded up along discrete fold lines that probably were genetically determined. A pneumatic retrophalangeal wedge behind the antebrachium through at least wing phalanx 3 streamlined the transition between the thick wing spar and thin patagium.

This second contribution on Rhamphorhynchus based on an acid-prepared specimen provides a detailed description of the braincase, concentrating on the broken skull and its hollow bones, aiming to ga...

In fossilised vertebrates, the presence of soft tissues is the most obvious way to determine aspects of anatomy and functional morphology; however, occurrences are rare and other lines of evidence must be sought to indicate its extent and strength. For example, pterosaurs possessed a large wing membrane that enabled powered flight but other tissues are not widely preserved. A semi-quantitative analysis comparing skeletal articulation and completeness of the pterodactyloid Pterodactylus and non-pterodactyloid pterosaur Rhamphorhynchus from Solnhofen-type deposits implies there were anatomical differences between soft-tissue structure and attachments articulating skeletal joints of each. Typically, skeletons of Pterodactylus disarticulate to a greater extent than those of Rhamphorhynchus, which in turn suggests decay progressed to more advanced states in the former. However, this generalisation masks a mosaic of differences between different body parts, for example Rhamphorhynchus tends to lose the wings as complete units but retains a complete and still articulated tail in a greater number of specimens than Pterodactylus.

The highly pneumatic skeleton of the extinct flying pterosaurs suggests that they would float high up on open water, but in a posture rather different to that of birds. However, the exact posture of the body and head remains unknown and would be critical for an ocean going pterosaur forced onto the waters' surface or animals that alighted to feed. Using computational methods with recent models and body mass estimates for four pterosaur genera—Dimorphodon, Rhamphorhynchus, Pteranodon and Dsungaripterus we show that the floating posture of pterodactyloid pterosaurs led to the head, neck and body being horizontal with the ventral 1/4 to 1/3 being immersed, and the external nares being almost at, or potentially partially below, the waterline that could have left them vulnerable to drowning. The floatation methods were verified using a model of a Canada goose (Branta canadensis) that is able to successfully replicate the expected orientation and depth of immersion of the bird. While there is convincing ev'idence for a number of pterosaurs foraging in marine and freshwater environments, these results suggest that many did not regularly rest on the surface of the water and if immersed would need to take off again rapidly. The high numbers of fossils of juvenile pterosaurs compared to the terrestrial Mesozoic dinosaurs suggest that this may be linked to their floating posture.

We present an annotated and illustrated catalogue of all original fossils, casts, and sculpted replicas of pterosaur specimens from the Upper Jurassic Solnhofen limestones of southern Germany that are housed at Carnegie Museum of Natural History (Pittsburgh, Pennsylvania, U.S.A.). The museum obtained its substantial Solnhofen pterosaur fossil collection—almost certainly the largest currently held outside of Europe—as part of its purchase of the vast private collection of the Belgian Baron Ernest de Bayet in 1903. Original fossils include six partial to nearly complete skeletons and a beautifully preserved skull of the rhamphorhynchine Rhamphorhynchus muensteri (Goldfuss, 1831), two skeletons of the ctenochasmatid pterodactyloid Aurorazhdarcho micronyx (von Meyer, 1856), and one large pterodactyloid partial appendicular skeleton of indeterminate affinity. Three of the fossils preserve significant soft tissues, and one of these is also among the very few specimens of Rhamphorhynchus von Meyer, 1847...

A previously undescribed and near-complete specimen of the non-pterodactyloid pterosaur Rhamphorhynchus is briefly described. Although purchased in 1878 and held in a public collection in Dublin, Ireland ever since, this specimen has never been described and was not even mentioned in the literature until 2010.

Based on comparative anatomical, morphological, and phylogenetic considerations the potential of pterosaurs for cranial kinesis is assessed. Our investigation shows that whereas skeletally mature derived pterodactyloids have completely fused, rigid and doubtlessly akinetic skulls, skeletally immature derived pterodactyloids and more basal pterosaurs possess key features in the morphology of their otic and basal joints that are suggestive of cranial kinesis, namely streptostyly. In addition, pterosaurs exhibit an evolutionarily informative trend in the degree of cranial ossification, where it is low in most nonpterodactyloids (here named bifenestratans), intermediate in Rhamphorhynchus and Archaeopterodactyloidea, and high in derived pterodactyloids. Incomplete fusion could also indicate loose connections between skull elements. However, another crucial anatomical requirement of a kinetic skull, the permissive kinematic linkage is absent in all pterosaurian taxa. The fact, that the presence of permissive kinematic linkages in the skull is also a prerequisite of all types of cranial kinesis, provides hard evidence that all members of Pterosauria had akinetic skulls. Thus, the presence of the morphological attributes indicative of intracranial movements in some pterosaurs must be explained on grounds other than real potential for cranial kinesis. It could either be of mechanical or ontogenetic importance, or both. Alternatively, it might be considered as the morphological remnant of a real, kinetic skull possessed by the diapsid ancestors of pterosaurs. Anat Rec, , 2011. © 2011 Wiley-Liss, Inc.

Body masses for 14 species of pterosaur spanning four orders of magnitude were estimated using three-dimensional, digital models. The modeled taxa comprised seven paraphyletic ‘rhamphorhynchoids’: Anurognathus ammoni, Dimorphodon macronyx, Eudimorphodon ranzii, Jeholopterus ningchengensis, Preondactylus buffarinii, Rhamphorhynchus muensteri, and Sordes pilosus; and seven pterodactyloids: Anhanguera santanae, Dsungaripterus weii, Pteranodon longiceps, Pterodaustro guinazui, Pterodactylus sp., Quetzalcoatlus northropi, Tupuxuara longicristatus. The reliability of the mass estimation methods were tested with equivalent models of six extant species of bird with masses that spanned three orders of magnitude. The close agreement between model bird mass estimates and those of the living forms provides a level of confidence in the results obtained for the extinct pterosaurs. The masses of the axial body regions (tail, trunk, neck, head), limbs, and patagia of the pterosaurs were individually estimated an...

Continuing studies of Neotropical Goodyerinae have revealed that three transfers are required in the genus Aspidogyne. Furthermore, the descriptions of 38 new taxa are required in the genera Aspidogyne (3), Kreodanthus (4), Ligeophila (one species, one variety), and Microchilus (28 species, one subspecies). The genus Rhamphorhynchus is considered to be congeneric with Aspidogyne. Microchilus glanduliferus is considered to be conspecific with M. campanulatus. Extensions of distribution are reported for three species. Illustrations are provided for 40 of the 45 taxa treated.

A new complete and fully articulated specimen of the anurognathid pterosaurAnurognathus ammoni from the Upper Jurassic Solnhofen Limestone of southern Germany provides new information about the species. The skull is broader than long and quite tall. The naris and antorbital fenestra are both small and anteriorly placed, whereas the orbit is very large. The palatal elements are slender struts of bone separating large openings. The tail is short, but is neither pygostyle-like nor like that of pterodactyloids. The wingfinger, unlike that of almost all pterosaurs, is reduced to three phalanges. Pedal digit V bears two long phalanges. Reexamination of the holotype specimen revealed evidence of bony bumps on the premaxilla and dentary that may have been associated with a fringe of bristles around the mouth.Anurognathus and the other anurognathids were probably adapted to aerial insectivory in low light conditions like extant caprimulgids and insectivorous bats, and may have spent little time on the ground. The taxonomy of the Anurognathidae is reviewed and new diagnoses are presented. A cladistic analysis supports the interpretation that the Anurognathidae is the sister-group to all other pterosaurs.

The second pterosaur genus to be established, Rhamphorhynchus von Meyer, 1847 , has historically been used as a wastebasket material. Several species have been erected for fossils found in Europe and Africa, the majority of which are based on non-diagnostic material. Following Bennett's (1996) review of its taxonomy, Rhamphorhynchus is generally regarded as a monospecific taxon restricted to the Late Kimmeridgian and Tithonian of Southern Germany. Here we describe a disarticulated but complete right pterosaur wing, MJML K-1597 from the Kimmeridge Clay Formation of England. Based on a combination of morphology and statistical analysis, MJML K-1597 can safely be referred to Rhamphorhynchus , making it the first diagnostic Rhamphorhynchus specimen from outside of Germany. Furthermore, based on the unique length ratio between wing phalanx 1 and wing phalanx 2, MJML K-1597 can be referred to a new species of Rhamphorhynchus .

Histological evidence of the bones of pterosaurs and dinosaurs indicates that the typically large forms of these groups grew at rates more comparable to those of birds and mammals than to those of other living reptiles. However, Scutellosaurus, a small, bipedal, basal thyreophoran ornithischian dinosaur of the Early Jurassic, shows histological features in its skeletal tissues that suggest relatively lower growth rates than in those of larger dinosaurs. In these respects Scutellosaurus, like other small dinosaurs such as Orodromeus and some basal birds, is more like young, rapidly growing crocodiles than larger, more derived ornithischians (hadrosaurs) and all saurischians (sauropods and theropods). Similar patterns can be seen in small, mostly basal pterosaurs such as Eudimorphodon and Rhamphorhynchus. However, superficial similarities to crocodile bone growth belie some important differences, which are most usefully interpreted in phylogenetic and ontogenetic contexts. Large size evolved second...

Statistical analyses of measurement data and morphological studies of pterosaur fossils from the Upper Jurassic Solnhofen Limestone of Germany reveal the presence of year-classes resulting from rep...

A statistical and morphological study of the pterosaurRhamphorhynchusfrom the Solnhofen Limestone of Germany shows that specimens fall into discrete size-classes that are year-classes resulting from seasonal mortality or preservation of specimens. Taxonomic characters used in the past to separate species ofRhamphorhynchusare all related to size and ontogeny, and all specimens belong to a single species,R. muensteri.Thus, the collections ofRhamphorhynchusprovide an unequaled record of the growth and development of a Jurassic rhamphorhynchoid pterosaur.Rhamphorhynchusdid not have rapid determinate growth; the growth rate was comparable to that of extant crocodilians, and growth continued over the course of at least three years after individuals began to fly.

Associations of large vertebrates are exceedingly rare in the Late Jurassic Solnhofen Limestone of Bavaria, Southern Germany. However, there are five specimens of medium-sized pterosaur Rhamphorhynchus that lie adjacent to the rostrum of a large individual of the ganoid fish Aspidorhynchus. In one of these, a small leptolepidid fish is still sticking in the esophagus of the pterosaur and its stomach is full of fish debris. This suggests that the Rhamphorhynchus was seized during or immediately after a successful hunt. According to the fossil record, Rhamphorhynchus frequently were accidentally seized by large Aspidorhnychus. In some cases the fibrous tissue of the wing membrane got entangled with the rostral teeth such that the fish was unable to get rid of the pterosaur. Such encounters ended fatally for both. Intestinal contents of Aspidorhynchus-type fishes are known and mostly comprise fishes and in one single case a Homoeosaurus. Obviously Rhamphorhynchus did not belong to the prey spectrum of Aspidorhynchus.

BackgroundThe 'Solnhofen Limestone' beds of the Southern Franconian Alb, Bavaria, southern Germany, have for centuries yielded important pterosaur specimens, most notably of the genera Pterodactylus and Rhamphorhynchus. Here we describe a new genus of non-pterodactyloid pterosaur based on an extremely well preserved fossil of a young juvenile: Bellubrunnus rothgaengeri (gen. et sp. nov.).Methodology/principal findingsThe specimen was examined firsthand by all authors. Additional investigation and photography under UV light to reveal details of the bones not easily seen under normal lighting regimes was completed.Conclusions/significanceThis taxon heralds from a newly explored locality that is older than the classic Solnhofen beds. While similar to Rhamphorhynchus, the new taxon differs in the number of teeth, shape of the humerus and femur, and limb proportions. Unlike other derived non-pterodacytyloids, Bellubrunnus lacks elongate chevrons and zygapophyses in the tail, and unlike all other known pterosaurs, the wingtips are curved anteriorly, potentially giving it a unique flight profile.

Background Rhamphorhynchus from the Solnhofen Limestones is the most prevalent long tailed pterosaur with a debated life history. Whereas morphological studies suggested a slow crocodile-like growth strategy and superprecocial volant hatchlings, the only histological study hitherto conducted on Rhamphorhynchus concluded a relatively high growth rate for the genus. These controversial conclusions can be tested by a bone histological survey of an ontogenetic series of Rhamphorhynchus. Methodology/Principal Findings Our results suggest that Bennett's second size category does not reflect real ontogenetic stage. Significant body size differences of histologically as well as morphologically adult specimens suggest developmental plasticity. Contrasting the ‘superprecocial hatchling’ hypothesis, the dominance of fibrolamellar bone in early juveniles implies that hatchlings sustained high growth rate, however only up to the attainment of 30–50% and 7–20% of adult wingspan and body mass, respectively. The early fast growth phase was followed by a prolonged, slow-growth phase indicated by parallel-fibred bone deposition and lines of arrested growth in the cortex, a transition which has also been observed in Pterodaustro. An external fundamental system is absent in all investigated specimens, but due to the restricted sample size, neither determinate nor indeterminate growth could be confirmed in Rhamphorhynchus. Conclusions/Significance The initial rapid growth phase early in Rhamphorhynchus ontogeny supports the non-volant nature of its hatchlings, and refutes the widely accepted ‘superprecocial hatchling’ hypothesis. We suggest the onset of powered flight, and not of reproduction as the cause of the transition from the fast growth phase to a prolonged slower growth phase. Rapidly growing early juveniles may have been attended by their parents, or could have been independent precocial, but non-volant arboreal creatures until attaining a certain somatic maturity to get airborne. This study adds to the understanding on the diversity of pterosaurian growth strategies.

Despite being known for nearly two centuries, new specimens of the derived non-pterodactyloid pterosaur Rhamphorhynchus continue to be discovered and reveal new information about their anatomy and palaeobiology. Here we describe a specimen held in the collections of the Royal Tyrrell Museum of Palaeontology, Alberta, Canada that shows both preservation and impressions of soft tissues, and also preserves material interpreted as stomach contents of vertebrate remains and, uniquely, a putative coprolite. The specimen also preserves additional evidence for fibers in the uropatagium.

A heavily compressed, but nearly complete fossil skeleton recovered from the Middle/Upper Jurassic Tiaojishan Forma-tion of Mutoudeng, Qinglong County, Hebei Province, China, represents a new genus and species of long-tailed pterosaur, Qinglongopterus guoi gen. et sp. nov. The holotype and only known specimen has an estimated forelimb length of 0.18m. The new taxon is distinguished by a relatively short skull, a remarkably short pteroid with a distinctive knob-like distalexpansion, and a prepubis with a relatively slender distal process. Phylogenetic analysis demonstrates that Qinglongopter- us is a member of Rhamphorhynchidae, exhibiting many of the unique character states found in members of this clade. Qinglongopterus is strikingly similar to Rhamphorhynchus and more closely related to this taxon than to any other rham-phorhynchine, this pairing is supported by morphometric data and several synapomorphies (short, broad nasal process ofthe maxilla; forelimb length more than four times that of the hind limb; wing-phalanx one more than twice the length ofthe tibia). Qinglongopterus demonstrates that the highly derived skeletal morphology of Rhamphorhynchus, known onlyfrom the latest Jurassic (Tithonian) of Europe, had already appeared by the start of the Late Jurassic. This hints at evolu-tionary stasis in Rhamphorhynchinae, a phenomenon seemingly also present in two other clades of basal pterosaurs,Anurognathidae and Scaphognathinae, and contrasting sharply with basal monofenestratans which appear to have undergone extensive evolutionary change during the same interval.

[Plate V.] I May state, by way of introduction, that I am indebted to my friend Professor O. C. Marsh for the correct determination of the interesting reptilian bones forming the subject of the present communication. I. Ornithosaurian Quadrates . When engaged in compiling Part I. of the ‘British Museum Catalogue of Fossil Reptilia and Amphibia,’ I was considerably puzzled with three imperfect bones from the Kimeridge Clay of Weymouth. Eventually I considered that they represented a peculiarly modified ulnar metacarpal of an Ornithosaurian; and they were accordingly entered at page 41 of the volume cited (Nos. 43034, 44183, and 41179) as the distal extremities of that bone. It was mentioned at page 40 of the same volume that these bones differed from normal specimens of the ulnar metacarpal in having a flat bony plate attached to one of their lateral surfaces, which I considered might have aided in the support of the patagium. The resemblance of the free trochlear extremity of these bones to that of the distal extremity of the ulnar metacarpal of an Ornithosaurian is, indeed, very striking; but, on seeing them, Professor Marsh at once said that they were Ornithosaurian quadrates. On comparison with the quadrate of the skeleton of Rhamphorhynchus Cuvieri preserved in the Museum, and also with that of Scaphognathus Purdoni†, it is quite evident that they belong to the right side of the skull. The distal extremity of each forms a deeply-grooved oblique trochlea, above which there is a nearly quadrangular shaft. To the

Since the description of the fossils belonging to this species of Pterosaurian which originally came into my possession, I have met with so much additional material, that I have thought it better completely to remodel the present Memoir, than to add the subsequently acquired information in cumbrous notes. Some time ago, the Earl of Ducie was good enough to place in my hands, for description, a portion of a lower jaw, about inches in length, which was obtained from a quarry known by the name of ldSmith9s Quarry,” at Sarsden, near Chipping Norton, in Oxfordshire. Bones of Pterosaurians abound in this locality, associated with remains of Megalosaurus and of Oolitic fishes; and Lord Ducie considers that the beds in which his fossil was discovered are the representative of the Stonesfield slate. In this conclusion, I find, my colleagues of the Geological Survey concur. The symphysial part of the lower jaw in question, and the whole of what remains of the right ramus, are extremely well preserved (Pl. XXIV. figs. l a , 1 b .); but the inferior part of the left ramus is broken away at a distance of about an inch behind the symphysis. The latter measures of an inch in length, and exhibits no suture. Its posterior boundary is nearly a quarter of an inch thick and looks downwards as well as backwards. The distance between the two edges of the rami opposite the posterior extremity of the symphysis is of an inch, the depth of a ramus measured

Mr friend Mr. Thomas Jesson recently forwarded to me a few small associated bones obtained from the Oxford Clay of St. Ives, Huntingdonshire, which are of a certain amount of interest as being the only specimens referable to a Pterodactyle hitherto described from these deposits in England, or, indeed, so far as I am aware, in any other part of Europe. The specimens comprise seven vertebrae, portions of the ilia and ischia of both sides; one femur and the distal portion of the corresponding bone of the opposite side; part of a bone, probably from the shaft of the tibia; and two undetermined fragments. When they came into my hands they were partially bedded in their native clay, and their broken surfaces show the pyritous impregnation so characteristic of Oxfordian specimens. The Ornithosaurian nature of the specimens is at once shown by the hollow shafts of the long bones and the structure of the vertebrae, the latter having procœlous centra, with complete obliteration of the neuro-central suture. The two fragments of the femur (fig. 3), which I have placed in apposition, do not exactly fit together, so that there may be a portion missing from the middle of the shaft, and it is quite possible that I have not put the proper distal half in apposition with the proximal one. The bones indicate an individual of somewhat smaller size than the examples of the Lower-Kimeridgian Rhamphorhynchus Gemmingi figured by Professor von Zittel in the ‘Palaeontographica,’ vol. xxix. pl. xii. The

Direct evidence of successful or failed predation is rare in the fossil record but essential for reconstructing extinct food webs. Here, we report the first evidence of a failed predation attempt by a pterosaur on a soft-bodied coleoid cephalopod. A perfectly preserved, fully grown soft-tissue specimen of the octobrachian coleoid Plesioteuthis subovata is associated with a tooth of the pterosaur Rhamphorhynchus muensteri from the Late Jurassic Solnhofen Archipelago. Examination under ultraviolet light reveals the pterosaur tooth is embedded in the now phosphatised cephalopod soft tissue, which makes a chance association highly improbable. According to its morphology, the tooth likely originates from the anterior to middle region of the upper or lower jaw of a large, osteologically mature individual. We propose the tooth became associated with the coleoid when the pterosaur attacked Plesioteuthis at or near the water surface. Thus, Rhamphorhynchus apparently fed on aquatic animals by grabbing prey whilst flying directly above, or floating upon (less likely), the water surface. It remains unclear whether the Plesioteuthis died from the pterosaur attack or survived for some time with the broken tooth lodged in its mantle. Sinking into oxygen depleted waters explains the exceptional soft tissue preservation.