"Acanthostega " is a partially aquatic tetrapod with developed limbs that shares features common with the earlier tetrapods, " Panderichthys " and " Eusthenopteron ".
12.
Secondly, after preparation of its pectoral fins, the internal limb skeleton showed closer resemblances to that of the elpistostegalians than to other more generalised tetrapodomorph fishes like " Eusthenopteron ".
13.
Various foramina on the humeral surfaces are very similar to those seen in " Ichthyostega ", " Acanthostega ", and lobe-finned fishes like " Eusthenopteron ".
14.
Elasmoid scales are thin, imbricated scales composed of a layer of dense, lamellar bone called isopedine, above which is a layer of tubercles usually composed of bone, as in " Eusthenopteron ".
15.
The layer of dentine that was present in the first sarcopterygians is usually reduced, as in the extant coelacanth, or entirely absent, as in extant lungfish and in the Devonian " Eusthenopteron ".
16.
Early tetrapods like " Ichthyostega " and " Acanthostega " differed from earlier tetrapodomorphs such as " Eusthenopteron " or " Panderichthys " in their increased adaptations for life on land.
17.
Nouvelle's graphic seal is a world globe overlaid by " Eusthenopteron foordi ", whose fossil discovery brought worldwide fame to the Miguasha National Park, now a UNESCO World Heritage Site within the municipality.
18.
He has also analysed the basic structure of the paired limbs by comparing the pectoral and pelvic fins of the " Eusthenopteron " with the hindleg of the Devonian tetrapod " Ichthyostega " and embryonic humans.
19.
In even the smallest known specimen of " Eusthenopteron foordi " ( at 29 mm ), the lepidotrichia cover all of the fins, which does not happen until after metamorphosis in genera like " Polyodon ".
20.
They are present in some lobe-finned fishes : coelacanths, all extant and some extinct lungfishes, some tetrapodomorphs like " Eusthenopteron ", amiids, and teleosts, whose cycloid and ctenoid scales represent the least mineralized elasmoid scales.
