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1
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The extent of the pterosaur flight membrane

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Elgin R., Hone D., Frey E.
Acta Palaeontologica Polonica
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2011
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tom 56
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nr 1
The shape and extent of the membranous brachioptagium in pterosaurs remains a controversial topic for those attempting to determine the aerodynamic performance of the first vertebrate fliers. Various arguments in favour of the trailing edge terminating against either the torso or hip, the femur, the ankle, or different locations for various taxa, has resulted in several published reconstructions. Uncertainty over the correct model is detrimental to both aerodynamic and palaeoecological studies that are forced to simultaneously consider multiple and highly variable configurations for individual taxa. A review of relevant pterosaur specimens with preserved soft tissues or impressions of the wing membrane, however, strongly suggests that the trailing edge of the wing extended down to the lower leg or ankle in all specimens where the brachiopatagium is completely preserved. This configuration is seen across a phylogenetically broad range of pterosaurs and is thus likely to have been universally present throughout the Pterosauria. Support for opposing hypotheses where the trailing edge terminates against the body, hip, or knee are based on several specimens where the wing membrane is either incomplete or has undergone post−mortem contraction. An ankle attachment does not rule out a high aspect ratio wing as the curvature of the trailing edge and the ratio of the fore to hind limbs also play a major role in determining the final shape of the membrane.
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Two bone fragments of ornithocheiroid pterosaurs from the Cenomanian of Volgograd region, Southern Russia

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Averianov A. O., Kurochkin E. N., Pervushov E. M., Ivanov A. V.
Acta Palaeontologica Polonica
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2005
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tom 50
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nr 2
Two pterosaur bone fragments, a distal humerus and a distal femur, from the upper Cenomanian of the Volgograd Region in the Don River basin of southern Russia are reported. Although fragmentary, these bones come from mature individuals and are exceptionally well and three−dimensionally preserved, allowing a detailed description of their anatomy. Both specimens can be referred to a middle−sized ornithocheiroid pterosaur with a reconstructed wingspan of about 4 m. The humerus shows affinities with Istiodactylus from the Barremian of England, whereas the femur fragment is not identifiable beyond Ornithocheiroidea indet.
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New information on the pterosaur Tupandactylus imperator, with comments on the relationships of Tapejaridae

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Pinheiro F. L., Fortier D. C., Schultz C. L., Andrade,de J. A. F. G., Bantim R. A. M.
Acta Palaeontologica Polonica
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2011
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tom 56
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nr 3
A new specimen of Tupandactylus imperator, comprising an incomplete skull with associated lower jaw, is described. The material is the best preserved specimen of this species known so far and provides new information on the anatomy of this pterodactyloid pterosaur, especially with respect to the morphology of the lower jaw, the first one formally described for the species. Also, the new specimen shows an extensive preservation of soft tissues such as the soft−tissue component of the headcrest, ramphoteca associated with the premaxillae and lower jaw, as well as probable pycnofibres. A phylogenetic analysis was performed in order to test the relationships of the taxon within Tapejaridae. The results of the analysis support Tapejaridae, as well as monophyly of Tapejarinae and Thalassodrominae.
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The first discovery of pterosaurs from the Upper Cretaceous of Mongolia

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Watabe M., Tsuihiji T., Suzuki S., Tsogtbaatar K.
Acta Palaeontologica Polonica
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2009
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tom 54
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nr 2
231-242
Cervical vertebrae of azhdarchid pterosaurs were discovered in two Upper Cretaceous (Baynshire Suite) dinosaur localities, Bayshin Tsav and Burkhant, in the Gobi Desert. These are the first discoveries of pterosaur remains in the Upper Cretaceous of Mongolia. The Burkhant specimen includes a nearly complete atlas−axis complex, which has rarely been described in this clade of pterosaurs. Although all elements comprising this complex are fused together, a wing−like atlas neural arch is still discernable. The postzygapophyseal facet of the axis is long anteroposteriorly and convex dorsally, and would likely have allowed a fairly large range of dorsoventral flexion at the axis−third cervical joint unlike in other well−known ornithocheiroids such as Pteranodon and Anhanguera. Both Mongolian localities represent inland, terrestrial environments, which were apparently not typical habitats of pterosaurs, thus adding further evidence for the ubiquity of Azhdarchidae during the Late Cretaceous.
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A new monofenestratan pterosaur from the Kimmeridge Clay Formation (Kimmeridgian, Upper Jurassic) of Dorset, England

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Martill D. M., Etches S.
Acta Palaeontologica Polonica
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2013
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tom 58
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nr 2
A specimen of slender skulled monofenestratan pterosaur from the Upper Jurassic Kimmeridge Clay Formation of Dorset, UK, is referred to the new genus and species Cuspicephalus scarfi. The dentition and posterior skull morphology suggest affinities with Darwinopterus, but a close relationship cannot be proved. There are also some similarities with the pterodactyloid Germanodactylus cristatus, but the presence of teeth on the distal rostrum excludes it from that genus. Pterosaur remains are rare in the Upper Jurassic of the UK and this specimen represents the first significant cranial remains of a pterosaur from the Kimmeridge Clay Formation, and possibly the first non−pterodactyloid monofenestratan outside China.
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The first dsungaripterid pterosaur from the Kimmeridgian of Germany and the biomechanics of pterosaur long bones

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Fastnacht M.
Acta Palaeontologica Polonica
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2005
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tom 50
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nr 2
A partial vertebral column, pelvis and femora of a newly discovered pterosaur are described. The remains from the Upper Jurassic (Kimmeridgian) of Oker (northern Germany) can be identified as belonging to the Dsungaripteridae because the cross−sections of the bones have relatively thick walls. The close resemblance in morphology to the Lower Cretaceous Dsungaripterus allows identification of the specimen as the first and oldest record of dsungaripterids in Central Europe. Furthermore, it is the oldest certain record of a dsungaripterid pterosaur world wide. The biomechanical characteristics of the dsungaripterid long bone construction shows that it has less resistance against bending and torsion than in non−dsungaripteroid pterosaurs, but has greater strength against compression and local buckling. This supports former suggestions that dsungaripterids inhabited continental areas that required an active way of life including frequent take−off and landing phases. The reconstruction of the lever arms of the pelvic musculature and the mobility of the femur indicates a quadrupedal terrestrial locomotion.
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