Remarkably well-preserved soft tissues in Mesozoic fossils have yielded substantial insights into the evolution of feathers1. New evidence of branched feathers in pterosaurs suggests that feathers originated in the avemetatarsalian ancestor of pterosaurs and dinosaurs in the Early Triassic2, but the homology of these pterosaur structures with feathers is controversial3,4. Reports of pterosaur feathers with homogeneous ovoid melanosome geometries2,5 suggest that they exhibited limited variation in colour, supporting hypotheses that early feathers functioned primarily in thermoregulation6. Here we report the presence of diverse melanosome geometries in the skin and simple and branched feathers of a tapejarid pterosaur from the Early Cretaceous found in Brazil. The melanosomes form distinct populations in different feather types and the skin, a feature previously known only in theropod dinosaurs, including birds. These tissue-specific melanosome geometries in pterosaurs indicate that manipulation of feather colour—and thus functions of feathers in visual communication—has deep evolutionary origins. These features show that genetic regulation of melanosome chemistry and shape7–9 was active early in feather evolution.

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<p>Este trabalho é resultado de um estudo de campo realizado na Falésia do Cabo Branco (João Pessoa, Paraíba – Brasil) e visa apresentar um esboço do perfil estratigráfico dessa unidade geológica, que faz parte da Formação Barreiras (Plio-Pleistoceno - entre 2 milhões e 588 mil e 11 mil e 500 anos). A pesquisa teve um caráter descritivo e explicativo e se baseou em coleta de amostras de estratos da falésia para identificar sua composição mineralógica e sedimentológica de uma forma geral. Percebe-se que esse afloramento apresenta depósitos diversos, tanto de origem fluvial, em sua parte basal, quanto de origem eólica no seu topo, e crostas lateríticas. A partir dessas observações montou-se um esboço do perfil estratigráfico com intuito didático para subsidiar estudos nas áreas de estratigrafia do litoral paraibano.</p>

The posterior part of a skull from a tapejarid pterosaur was studied for the exceptional preservation of its soft-tissues. The specimen comes from the Early Cretaceous (Aptian) Crato Formation of northeastern Brazil. It shows a peculiar soft sagittal crest that gives new information about the anatomy and the diversity of tapejarids. The specimen lies on five limestone slabs. The bony part comprised the posterior part of the skull, with the braincase and one complex of three dorsally oriented and associated bony crests. The crest consists of a huge and elongated parietal crest, a trabecular frontal crest, and an occipital spine. The specimen preserves the posterior parts of the nasoantorbital fenestra and orbit. The soft cranial crest is characterized by a multilinear dorsal crest with almost parallel fibres, which curve posteriorly. Pigment organelles -melanosomes -were observed in the crest as well as 'hair-like' fibres (pycnofibres). They present diverse shapes and sizes, suggesting diverse colorations for the soft tissues. The new tapejarid shares certain features with the tapejarids Tupandactylus imperator and "Huaxiapterus" benxiensis, which include an elongated parieto-occipital crest. Nonetheless, it differs from Tupandactylus imperator and Ingridia navigans by the following characteristics: absence of a suprapremaxillary spine, very dorsally oriented posterior crests, as well as a specific morphology for the soft crest. Our specimen can therefore be assigned to a new taxon of Tapejaridae, a group previously reported from the Crato Formation.PeerJ Preprints | https://doi.org/10.7287/peerj.preprints.3138v1 | CC BY 4.0

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Pterosaurs thrived in and around water for 160 + million years but their take-off from water is poorly understood. A purportedly low floating position and forward centre of gravity barred pterosaurs from a bird-like bipedal running launch. Quadrupedal water launch similar to extant water-feeding birds and bats has been proposed for the largest pterosaurs, such as Anhanguera and Quetzalcoatlus. However, quadrupedal water launch has never been demonstrated in smaller pterosaurs, including those living around the Tethys Sea in the Late Jurassic Solnhofen Lagoon. Using Laser-Stimulated Fluorescence, we singled out aurorazhdarchid specimen MB.R.3531 that alone preserved specific soft tissues among more than a dozen well-preserved Solnhofen pterosaur specimens. These soft tissues pertain to primary propulsive contact surfaces needed for quadrupedal water launch (pedal webbing and soft tissues from an articulated forelimb) that permit robust calculations of its dynamic feasibility without the need to make assumptions about contact areas. A first-principles-based dynamics model of MB.R.3531 reveals that quadrupedal water launch was theoretically feasible and that webbed feet significantly impacted launch performance. Three key factors limiting water launch performance in all pterosaurs are identified, providing a foundation for understanding water launch evolution: available propulsive contact area, forelimb extension range and forelimb extension power about the shoulder.