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Rhamphorhynchus is one of the best-known pterosaurs, with well over 100 specimens being held in public collections. Most of these represent juvenile animals, and the adults known are typically around 1 m in wingspan. Here we describe a near complete skeleton, preserved partially in 3D, of an animal with a wingspan of around 1.8 m, that is considerably larger than other known specimens, and is among the largest known non-pterodactyloid pterosaurs. This animal shows differences in the anatomy not seen in smaller specimens, revealing details of late-stage ontogeny in this genus. The specimen exhibits a disproportionate reduction in the size of the orbit and increase in the size of the lower temporal fenestra, a reduction in the proportional mandibular symphysis, and unusually laterally flattened teeth, which may point to a changing diet as these animals grew. These features show a transition from smaller to larger specimens of Rhamphorhynchus and also appear in other large specimens of rhamphorhyhchines and point to a consistent pattern in their development. [ABSTRACT FROM AUTHOR]

For over a century, there was a major gap in our understanding of the evolution of the flying Mesozoic reptiles, the pterosaurs, with a major morphological gap between the early forms and the derived pterodactyloids. 1 Recent discoveries have found a cluster of intermediate forms that have the head and neck of the pterodactyloids but the body of the early grade, 2 yet this still leaves fundamental gaps between these intermediates and both earlier and more derived pterosaurs. Here, we describe a new and large Jurassic pterosaur, Skiphosoura bavarica gen. et sp. nov., preserved in three dimensions, that helps bridge the gap between current intermediate pterosaurs and the pterodactyloids. A new phylogeny shows that there is a general progression of key characteristics of increasing head size, increasing length of neck and wing metacarpal, modification to the fifth toe that supports the rear wing membrane, and gradual reduction in tail length and complexity from earlier pterosaurs into the first pterodactyloids. This also shows a clear evolution of the increasing terrestrial competence of derived pterosaurs. Furthermore, this closes gaps between the intermediates and their ancestors and descendants, and it firmly marks the rhamphorhynchines and ctenochasmatid clades as, respectively, being the closest earliest and latest groups to this succession of transitional forms. • A new pterosaur, Skiphosoura bavarica , is named from the Jurassic of Germany • The specimen is much larger than other known forms and is preserved in three dimensions • The Skiphosoura helps document the transition from early pterosaurs to the pterodactyloids • The tail is short but retains the supporting structures of earlier forms Hone et al. describe and name a new pterosaur, Skiphosoura bavarica , from the Jurassic of Southern Germany that is unusually large for the time and well preserved in three dimensions. This specimen, coupled with a new phylogenetic analysis, shows the stepwise accumulation of numerous characteristics from the early pterosaurs through to the derived pterodactyloids. [ABSTRACT FROM AUTHOR]

The Crato Formation (Lower Cretaceous, Brazil) is a Konservat-Lagerstätte preserving a great number of exceptionally well-preserved insects. Here, we sought to explore the preservational modes of two abundant aquatic and terrestrial groups of this unit, mayflies and crickets. To better understand how exceptional is their preservation, we also present detailed data on the modes of preservation of mayflies from the renowned Solnhofen limestones (Upper Jurassic, Germany). For the Crato Formation, out of 234 fossil mayflies and crickets, ten specimens were additionally analyzed using scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM-EDS), energy and micro-energy dispersive X-ray fluorescence (EDXRF and μEDXRF), and μRaman spectroscopy. For the Solnhofen limestones, 85 adult mayflies were analyzed, and five of them were subjected to SEM-EDS and μEDXRF analyses. The Crato specimens preserve several external and internal microfeatures. The areas with the highest fidelity of preservation are characterized by smaller and more closely-packed crystals when compared to less-preserved parts. We also recovered microscopic features that suggest the presence of microbial mats during the fossilization process. All the analyzed Crato specimens are preserved by replacement of tissues with iron oxides after pyritization. Sulfur occurs scattered in some regions of the crickets, but is associated with low iron counts, which may indicate the presence of sulfates post-dating pyrite oxidation. Additionally, the orthopterans have calcium phosphate preserving some of their structures. Differing from Crato insects, Solnhofen mayflies are overall poorly preserved as mere imprints, and their micron-scale morphology is obliterated by coarse mineral growth, whereas tissues are obliterated by calcite crystals alone or in combination with globular material. There is an elevated concentration of Si, K, Ca, Ti, Mn, and Fe in comparison to the host rock, which may be related to a yet unknown mineral phase(s). Although the paleoenvironments of the Crato Formation and the Solnhofen limestones are different, there are similarities in the style of preservation of their vertebrates and in some of their paleoenvironmental conditions such as anoxic hypersaline bottom waters and deposition of laminated limestones. However, the same does not apply to the preservation of insects, specifically mayflies, which are poorly preserved in the Solnhofen limestones. [ABSTRACT FROM AUTHOR]

Rhamphorhynchus is one of the best-known pterosaurs, with well over 100 specimens being held in public collections. Most of these represent juvenile animals, and the adults known are typically around 1 m in wingspan. Here we describe a near complete skeleton, preserved partially in 3D, of an animal with a wingspan of around 1.8 m, that is considerably larger than other known specimens, and is among the largest known non-pterodactyloid pterosaurs. This animal shows differences in the anatomy not seen in smaller specimens, revealing details of late-stage ontogeny in this genus. The specimen exhibits a disproportionate reduction in the size of the orbit and increase in the size of the lower temporal fenestra, a reduction in the proportional mandibular symphysis, and unusually laterally flattened teeth, which may point to a changing diet as these animals grew. These features show a transition from smaller to larger specimens of Rhamphorhynchus and also appear in other large specimens of rhamphorhyhchines and point to a consistent pattern in their development.

The Crato Formation (Lower Cretaceous, Brazil) is a Konservat-Lagerstätte preserving a great number of exceptionally well-preserved insects. Here, we sought to explore the preservational modes of two abundant aquatic and terrestrial groups of this unit, mayflies and crickets. To better understand how exceptional is their preservation, we also present detailed data on the modes of preservation of mayflies from the renowned Solnhofen limestones (Upper Jurassic, Germany). For the Crato Formation, out of 234 fossil mayflies and crickets, ten specimens were additionally analyzed using scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM-EDS), energy and micro-energy dispersive X-ray fluorescence (EDXRF and µEDXRF), and µRaman spectroscopy. For the Solnhofen limestones, 85 adult mayflies were analyzed, and five of them were subjected to SEM-EDS and µEDXRF analyses. The Crato specimens preserve several external and internal microfeatures. The areas with the highest fidelity of preservation are characterized by smaller and more closely-packed crystals when compared to less-preserved parts. We also recovered microscopic features that suggest the presence of microbial mats during the fossilization process. All the analyzed Crato specimens are preserved by replacement of tissues with iron oxides after pyritization. Sulfur occurs scattered in some regions of the crickets, but is associated with low iron counts, which may indicate the presence of sulfates post-dating pyrite oxidation. Additionally, the orthopterans have calcium phosphate preserving some of their structures. Differing from Crato insects, Solnhofen mayflies are overall poorly preserved as mere imprints, and their micron-scale morphology is obliterated by coarse mineral growth, whereas tissues are obliterated by calcite crystals alone or in combination with globular material. There is an elevated concentration of Si, K, Ca, Ti, Mn, and Fe in comparison to the host rock, which may be related to a yet unknown mineral phase(s). Although the paleoenvironments of the Crato Formation and the Solnhofen limestones are different, there are similarities in the style of preservation of their vertebrates and in some of their paleoenvironmental conditions such as anoxic hypersaline bottom waters and deposition of laminated limestones. However, the same does not apply to the preservation of insects, specifically mayflies, which are poorly preserved in the Solnhofen limestones.

Ichthyosaurs from the Solnhofen Lagerstätte are among the only examples of soft tissue preservation in the major Middle Jurassic–middle Cretaceous family Ophthalmosauridae. However, few such specimens are currently described, and the taphonomical pathways for the preservation of soft tissue are not well understood. In order to answer this, two new ichthyosaur specimens, one nearly complete and one isolated tail, are described here. The nearly complete specimen is assigned to Aegirosaurus sp. It is accompanied by large amounts of incrustation pseudomorphs (epimorphs) of soft tissue preserved as apatite. It also preserves a nearly complete gastral basket, for the first time in ophthalmosaurids. Soft tissue samples were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) analysis. The analyses confirm the presence of apatite, with phosphate most likely derived from the body itself. [ABSTRACT FROM AUTHOR]

Ichthyosaurs from the Solnhofen Lagerstätte are among the only examples of soft tissue preservation in the major Middle Jurassic–middle Cretaceous family Ophthalmosauridae. However, few such specimens are currently described, and the taphonomical pathways for the preservation of soft tissue are not well understood. In order to answer this, two new ichthyosaur specimens, one nearly complete and one isolated tail, are described here. The nearly complete specimen is assigned to Aegirosaurus sp. It is accompanied by large amounts of incrustation pseudomorphs (epimorphs) of soft tissue preserved as apatite. It also preserves a nearly complete gastral basket, for the first time in ophthalmosaurids. Soft tissue samples were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) analysis. The analyses confirm the presence of apatite, with phosphate most likely derived from the body itself.