The axial skeleton of the Devonian tetrapod Ichthyostega

@article{Ahlberg2005TheAS,
  title={The axial skeleton of the Devonian tetrapod Ichthyostega},
  author={Per Erik Ahlberg and Jennifer Alice Clack and Henning Blom},
  journal={Nature},
  year={2005},
  volume={437},
  pages={137-140}
}
Ichthyostega was the first Devonian tetrapod to be subject to a whole-body reconstruction. It remains, together with Acanthostega, one of only two Devonian tetrapods for which near-complete postcranial material is available. It is thus crucially important for our understanding of the earliest stages of tetrapod evolution and terrestrialization. Here we show a new reconstruction of Ichthyostega based on extensive re-examination of original material and augmented by recently collected specimens… 
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113 Citations
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113 Citations

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Contrasting Developmental Trajectories in the Earliest Known Tetrapod Forelimbs

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It is inferred that Ichthyostega underwent greater locomotory terrestrialization during ontogeny and could be phylogenetically more basal than Acanthostega, which is generally considered the more primitive tetrapod.

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The skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica are presented, a transitional intermediate form between the ‘elpistostegids’ Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega.

A Marine Stem-Tetrapod from the Devonian of Western North America

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This new taxon, Tinirau clackae, demonstrates that substantial parallelism pervaded the early history of stem-tetrapods, raises additional questions about when digited sarcopterygians first evolved, and further documents that incipient stages of the terrestrial appendicular condition began when sarcoperygians still retained their median fins and occupied aquatic habitats.

The postcranial anatomy of Whatcheeria deltae and its implications for the family Whatcheeriidae

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Palaeontology: Between water and land

TLDR
A new reconstruction of Ichthyostega differs radically from previous versions in having a regionalized vertebral column that bears a striking resemblance to that of a mammal, suggesting that the four-legged fish could move on land using a bilaterally symmetrical ‘shuffling’ action.

Morphology of the earliest reconstructable tetrapod Parmastega aelidae

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Three-dimensionally preserved fossils of Parmastega aelidae, a newly described tetrapod from the earliest Famennian (Late Devonian) of Russia, provide detailed insights into the morphology and palaeobiology of the earliest tetrapods.

Limb‐bone histology of temnospondyls: implications for understanding the diversification of palaeoecologies and patterns of locomotion of Permo‐Triassic tetrapods

TLDR
This study presents the first palaeohistological study based on theoretical biomechanical considerations among a highly diversified group of early tetrapods, the temnospondyls, based on the quantification of microanatomical and histological parameters in the humerus and femur of nine genera.

The smallest known Devonian tetrapod shows unexpectedly derived features

TLDR
Brittagnathus is described from a single complete right lower jaw ramus recovered from the Acanthostega mass-death deposit in the upper part of the Britta Dal Formation of Stensiö Bjerg, Gauss Peninsula, East Greenland and suggests that diversification of ‘Carboniferous-grade’ tetrapods had already begun before the end of the Devonian and that the group was not greatly affected by the end-Devonian mass extinction.
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