Pennsylvanian Calamites?

[KCMOfossil]

This specimen was a surprise to me. At first glance, because of the delicate fibrous appearance and the wood color, I thought it was a modern piece of wood embedded in the middle of a boulder. Closer examination, however, revealed what you see in the pictures. This specimen is from the Winterset Limestone Member in the Kansas City Group, Pennsylvanian subsystem. It is about 1 cm long with a short branch off to the side. The specimen is split in half laterally and the pictures show the two halves that fit together. There were various brachiopods and half of a nice four-inch involutely coiled nautiloid (at least I think that is what it is) in the same boulder. The fossil is siliceous and has well-preserved, tiny fibers which are the color of wood. Although, it may be that the color is actually the same dusty red-brown or dusty purple as some other fossils in this member (mostly brachiopods). From the scant resources I have on hand for plant identification, I have guessed that it might be a Calamites. Any help with identification will be appreciated.

 

Russ

 

Russ

 

 

[Fossildude19]

I would vote no for Calamites. 

I don't see the parallel ribbing that you would normally see in Calamites.

 

The broken bit looks like a decorticated rachis of some plant.

Without finding it in association with any leaves, I'm not sure you could identify it any further than "plant remains, possible rachis. "

I wonder if @fiddlehead can make any pronouncements on this. 

Regards, 

[abyssunder]

I agree with Tim.

Possible plants : Pecopteris, Neuropteris, Cyclopertis, Cordaites, Lepidodendron and Calamites. FOSSILS OF THE KANSAS CITY GROUP - Dennis Whitney Dennisformation.pdf

[KCMOfossil]

Thanks to you both for your evaluation.  Abyssunder, the article you attached will really be helpful as I continue to collect in the Dennis formation.  An article I found here by searching for rachis has some pictures that show the vascular structure that is apparent in my specimen.

 

Russ

[Missourian]

It is likely Cordaites wood. I have posted some specimens here, which are all from the Winterset Limestone:

 

 

[doushantuo]

cordaites ,by someone who knows them inside out

http://actab.nm.cz/wp-content/static/article/2006_97.pdf

 

[doushantuo]

 

falcordaitbashfortarboresceni2005-RPP.pdf

[KCMOfossil]

The thread on cordiates is very nice--educational.  In fact, I moved a specimen from my pseudofossil shelf to my sparsely populated plant shelf based on the photos there.  Thanks, Missourian.

 

And thanks to you, doushantuo, for the link.  Quite valuable.

 

Russ