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Moythomasia

Moythomasia is an extinct genus of early ray-finned fish from the Devonian period of Europe and Australia.

Moythomasia was a small freshwater fish, long. It had relatively large eyes, presumably to find prey in murky water. Its body was covered in specialized ganoid scales; the upper side of each scale sported a small pin that perfectly fit into the hollow lower side of the next scale. This allowed the fish to be both armored and flexible.