Newer research has shown that it had an unusual anatomy, functioning more akin to a seal than a salamander, as previously assumed.

Computed tomography has revealed that Ichthyostega had a specialized ear, including a stapes with a unique morphology compared to other tetrapods or to any fish hyomandibula.

The lumbar vertebrae at the back of the trunk have strong muscle scars and neural spines which are bent forwards and decrease in size towards the hips.

The sacral vertebrae above the hips have fan-shaped neural spines that transition from forward-leaning to backward-leaning as they approach the tail.

Ichthyostega's skull seems more fish-like than that of Acanthostega, but had apelvic girdle morphology that seems stronger and better adapted to life on land.

It does, however, show that Ichthyostega may have ventured onto land on occasions, unlike contemporaneous limbed vertebrates, such as Elginerpeton and Obruchevichthys.

[9] Panderichthys Tiktaalik Elpistostege Elginerpeton Ventastega Acanthostega Ichthyostega Whatcheeriidae Colosteidae Crassigyrinus Baphetidae Crown group Tetrapoda

Early limbed vertebrates like Ichthyostega and Acanthostega differed from earlier tetrapodomorphs such as Eusthenopteron or Panderichthys in their increased adaptations for life on land.

Tetrapodomorphs used their bodies and tails for locomotion and their fins for steering and braking; Ichthyostega may have used its forelimbs for locomotion on land and its tail for swimming.Its massive ribcage was made up of overlapping ribs and the animal possessed a stronger skeletal structure, a largely fishlike spine, and forelimbs apparently powerful enough to pull the body from the water.

The hindlimbs were smaller than the forelimbs and unlikely to have borne full weight in an adult, while the broad, overlapping ribs would have inhibited side-to-side movements.