3 years ago
Looking for some help in identifying this fern to genus level if possible, so it can be posted to the emuseum. It is from the Mazon Creek fossil beds, near Morris, Illinois, USA. It is from the Francis Creek Shale, which if I recall correctly is Middle Pennsylvanian – Des Moinesian Stage. Any help would be much appreciated!
It looks like a Pecopteris fossil. There are a few species. P subcrenulata, P mazoniana, P aborescense. There’s also Lobatopteris lumuriana that look like Pecopteris.
I’m not sure how many of these are actually still valid. I’m leaning toward Pecopteris mazoniana for your specimen. I’d google Pecopteris fossils from mazon creek to find a positive ID.