A single leafy stem from the Middle or lowermost Upper Devonian Campo Chico Formation, Sierra de Perija, western Venezuela, is the first record of the important Devonian herbaceous lycophyte Leclercqia from South America, usually considered as part of western Gondwana. The seemingly cosmopolitan distribution of this genus is discussed in relation to coeval assemblages and palaeocontinental reco...

The extensional collapse of the Scandinavian Caledonides resulted in rapid tectonic denudation of the orogen, exhumation of highand ultra-high-pressure metamorphic rocks and provided a structural template for the formation of Devonian supra-detachment sedimentary basins. The geometry and intensity of the extensional deformation show considerable variation vertically in the crustal section as we...

The fossils assigned to the tetrapod stem group document the evolution of terrestrial vertebrates from lobe-finned fishes. During the past 15 years the phylogenetic structure of this stem group has remained remarkably stable, even when accommodating major new discoveries such as the elpistostegid Tiktaalik. Here we present a large tetrapodomorph fish from the Late Devonian of China that disrupt...

Due to morphological resemblance, polypterid fishes are used as extant analogues of Late Devonian lobe-finned sarcopterygians to identify the features that allowed the evolution of a terrestrial lifestyle in early tetrapods. Previous studies using polypterids showed how terrestrial locomotion capacity can develop, and how air ventilation for breathing was possible in extinct tetrapodomorphs. In...

Progressive biomineralization of a skeleton occurs during ontogeny in most animals. In fishes, larvae are poorly mineralized, whereas juveniles and adults display a progressively more biomineralized skeleton. Fossil remains primarily consist of adult specimens because the fossilization of poorly-mineralized larvae and juveniles necessitates exceptional conditions. The Miguasha Fossil-Lagerstätt...