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Lower jaws, lower tetrapods–a review based on the Devonian genus Acanthostega
The lower jaw of the Devonian tetrapod Acanthostega is described for the first time. Redescriptions are provided for the lower jaws of the elpistostegid Panderichthys , the Devonian tetrapods
An early tetrapod from ‘Romer's Gap’
  • J. Clack
  • Biology, Medicine
  • 4 July 2002
Pederpes is the earliest-known tetrapod to show the beginnings of terrestrial locomotion and was at least functionally pentadactyl, bridging the temporal, morphological and phylogenetic gaps that have hitherto separated Late Devonian and mid-Carboniferous tetrapOD faunas.
Pederpes finneyae, an articulated tetrapod from the tournaisian of Western Scotland
The postcranial skeleton of Pederpes shows several unique features, including the structure of the leading edges of the cleithrum and clavicle, the form of the rib flanges and a possible supernumerary digit on the manus.
Pholiderpeton scutigerum Huxley, an Amphibian from the Yorkshire Coal Measures
The evidence suggests that the eogyrinids, like the archeriids, were long-bodied with a presacral count of 40 and forelimb function in Pholiderpeton was more flexible than that proposed for the related Proterogyrinus.
An amniote-like skeleton from the Early Carboniferous of Scotland
A small, highly ossified, postcranial skeleton of a terrestrially adapted, amniote-like tetrapod from the Mid Viséan is reported, which shows the earliest known pentadactyl manus and pushes back the known occurrence of terrestrial vertebrates closer to the origin of tetrapods.
The neurocranium of Acanthostega gunnari Jarvik and the evolution of the otic region in tetrapods
Abstract The neurocranium of Acanthostega gunnari is described from several specimens, and is the first full description of a Devonian tetrapod braincase. It is shown to resemble the osteolepiform
The dermal skull roof of Acanthostega gunnari, an early tetrapod from the Late Devonian
  • J. Clack
  • Geology
    Transactions of the Royal Society of Edinburgh…
  • 1 March 2002
ABSTRACT The dermal skull roof of Acanthostega gunnari Jarvik is described in detail, giving new information on the anatomy, and new reconstructions of the skull in dorsal, lateral and occipital
The Scottish Carboniferous tetrapod Crassigyrinus scoticus (Lydekker)—cranial anatomy and relationships
A new reconstruction of the skull of Crassigyrinus scoticus (Lydekker) is provided, based on newly prepared material. A revised interpretation of the naris shows it in most respects to be like that
Three-dimensional limb joint mobility in the early tetrapod Ichthyostega
It is shown that Ichthyostega could not have employed typical tetrapod locomotory behaviours, such as lateral sequence walking, and was unlikely to have made some of the recently described Middle Devonian trackways.
Devonian climate change, breathing, and the origin of the tetrapod stem group.
  • J. Clack
  • Biology, Medicine
    Integrative and comparative biology
  • 1 October 2007
The diversification of the tetrapod stem group occurred during the late Middle through the Late Devonian, that is from the Givetian to Famennian stages about 385-365 million years ago, and plant diversification was at its most rapid, changing the character of the landscape and contributing, via soils, soluble nutrients, and decaying plant matter, to anoxia in all water systems.