Huge Mazon Creek tree fern plant fossil nodule? Does anyone know?

[KarenH]

I recently was given this fossil that belonged to my grandfather in Wisconsin. Can anyone help me positively identify it? He collected all kinds of things, including Indian Artifacts, Arrowheads, Stone Tools, Rocks and Gems, etc.

 

13" long

8.4 lbs.

 

Thank you!

Edited June 2, 2021 by KarenH

[Fossildude19]

Welcome to the Forum.  

Great fossil! 

Looks like Pecopteris sp. ? Maybe.

 

@Nimravis  @RCFossils  @fiddlehead  @paleoflor  @Mark Kmiecik

 

 

Check out RCFossils' gallery. 

 

[piranha]

Crenulopteris acadica

 

Wittry, J., Glasspool, I.J., Béthoux, O., Koll, R., Cleal, C.J. 2015

A Revision of the Pennsylvanian Marattialean Fern Lobatopteris vestita auct. and related species.

Journal of Systematic Palaeontology, 13(8):615-643  PDF LINK

[FossilDAWG]

2 hours ago, KarenH said:

I recently was given this fossil that belonged to my grandfather in Wisconsin. Can anyone help me positively identify it? He collected all kinds of things, including Indian Artifacts, Arrowheads, Stone Tools, Rocks and Gems, etc.

 

13" long

8.4 lbs.

 

Thank you!

Welcome to the Fossil Forum.

 

That is an amazing specimen!

 

Don

[fiddlehead]

I can't quite make out the venation. But from the little I can see of it, and the shape of the ultimate pinnae and pinnule shapes. In my opinion it's a Cyathocarpus arborea. The old name with the catch-all genus combined with an invalid species name was Pecopteris arborescens. 

 

Hope that clears up... something.

Jack 

Edited June 2, 2021 by fiddlehead

[piranha]

It sure looked like a good match......foiled again by another pesky pecopterid!

[Nimravis]

Gotta love the big concretions.

[Plantguy]

6 hours ago, piranha said:

It sure looked like a good match......foiled again by another pesky pecopterid!

Scott, I second that sentiment! They are only one of my undoings. 

Regards, Chris 

KarenH, thanks for sharing the wonderful specimen! Now that's a concretion and a half! 

 

Regards, Chris 

[Mark Kmiecik]

Pecopteris arborescens is what I would know it by. I'm not up on the changes and new names. I default to Jack's judgment, and Cyathocarpus arborea. Nice large specimen, of a size rarely found anymore. I recommend putting a double thickness of paper towel between the two halves when putting it away for storage if it isn't displayed. Otherwise the two halves rub against each other each time you pull them apart or put them together. Eventually you will make it disappear by "sanding" the two pieces against each other. This is the kind of specimen MC collectors search for, but only find occasionally.

[siteseer]

Seeing a nodule like that at a show was uncommon even 25 years ago.  A friend lucked out when a longtime collector sold him maybe 20 fern nodules that big at a bargain price around that time.  He didn't know what he had.  He took them to a show in Hollywood, CA and put out 5-7 of them and they sold instantly.  He wondered if he had underpriced them so he didn't put them all out.  I happened to visit him a few days after that and he showed me what he still had.  I advised him to keep one because it was so unusual:  one fern was about 9 inches long with another one about the same size criss-crossed behind it.  He had it on display in his house for years.  He doubled the price on the others and they all sold at the next show.

 

Jess

[Mark Kmiecik]

I have seen them close to 18" long and parts of stems and branches exceeding 3 feet. I'm trying to remember the name of the ESCONI member who displayed at least two dozen 12" or better at annual ESCONI shows. He would actively hunt as well as purchase/trade for the big stuff and his collection of beyond-museum-size-and-quality was stunning. I would stand there looking and drooling each year.

[KarenH]

Thank you everyone for your nice comments and insightful knowledge. I really appreciate it. I'm going to list this on online in the near future. Thanks again and good luck with your fossil hunting!