Fossilized fern

Species: Pecopteris sp., Neuropteris sp., Alethopteris sp., Sphenopteris sp.

Age: ~320-300 million years.

Period: Carboniferous.

Origin: Pennsylvania, United States.

Size: 14x6cm

Description: These ferns played a key role in the formation of coal deposits during the Carboniferous, as they grew in large quantities in swamps and wetlands.