Three-dimensional limb joint mobility in the early tetrapod Ichthyostega

A three-dimensional reconstruction and comparative analysis found that Ichthyostega lacked the limb long-axis rotations required for a typical lateral-sequence walk; this may reflect restricted early mobility or a specialization of Ichthyostega itself.

Ichthyostega is bounded here by specimens from Famennian Upper Devonian deposits of East Greenland used in the cited mobility study; this bounded sample context is not a global distribution or exact complete range.

The Ichthyostega mobility study analyses the genus as an early tetrapod and tests its limb mechanics against living analogues; the mechanical result is not a complete phylogenetic hypothesis.

The Ichthyostega specimens reconstructed in the cited study are from East Greenland Upper Devonian deposits; this named sample does not establish a global range.

Three-dimensional reconstruction of Ichthyostega limb joints found no long-axis rotations required for a typical lateral-sequence walk in the tested model, while retaining the possibility that this is a specialization of Ichthyostega.

The cited Ichthyostega mobility study constrains modeled limb motion but does not directly establish diet, habitat preference or observed locomotor behaviour for the genus.