Paleontologists suggest that it is representative of the transition between non-tetrapod vertebrates ( fish ) such as Panderichthys , known from fossils 380 million years old , and early tetrapods such as Acanthostega and Ichthyostega , known from fossils about 365 million years old .
It is part of the transition between fish such as Panderichthys , known from fossils 380 million years old , and early tetrapods such as Acanthostega and Ichthyostega , known from fossils about 365 million years old .