[4] Some 2,000 Eusthenopteron specimens have been collected from Miguasha, one of which was the object of intensely detailed study and several papers by paleoichthyologist Erik Jarvik between the 1940s and the 1990s.

It shares a similar pattern of skull roofing bones with stem tetrapoda forms such as Ichthyostega and Acanthostega.

Similarly, its elasmoid scales lack superficial odontodes composed of dentine and enamel; this loss appears to be a synapomorphy with more crownward tetrapodomorphs.

[11] Eusthenopteron differs significantly from some later Carboniferous tetrapods in the apparent absence of a recognized larval stage and a definitive metamorphosis.

[6] In even the smallest known specimen of Eusthenopteron foordi, with a length of 29 millimetres (1.1 in), the lepidotrichia cover all of the fins, which does not happen until after metamorphosis in genera like Polydon (the American paddlefish).