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Shamalama

Some mystery fern fossils from St. Clair

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Shamalama

Here are a couple of "old" pieces from St. Clair that I found. The first one is a faint trace that I think is Pectopteris but I find it so rarely at St. Clair I can't tell for sure. What is throwing me off is that the leaflets are getting longer as they progress along the rachis whereas I have always thought that Pectopteris had a consistent leaflet length along the whole leaf.

 

IMG_7056.thumb.jpg.9356d3e1fdfa604806de73ed8f58b63b.jpgIMG_7055.thumb.jpg.85cb0a19537fdd04e77639d291bd55d1.jpg

 

Then the second piece is a cluster of leaves/leaflets that don't match anything I've seen before. The tips of the leaves are not pointed enough for Alethopteris and not wide enough for Neuropteris.

IMG_7059.thumb.jpg.b5e883b6479e003df269640b9e3cce6c.jpg

IMG_7058.thumb.jpg.023fd08578478c7ae16e13ac2bde2590.jpg

 

Any suggestions are appreciated.

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GeschWhat

They are so beautiful! The obvious and only contribution I can make. :popcorn:

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Fossildude19

Hey Dave, great finds!

The first one reminds me of Lyginopteris

Maybe @fiddlehead or @fossilcrazy  @docdutronc @paleoflor will chime in. 

 

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Ludwigia

I'm no great authority on plants, but I do know that I have a Permian Pecopteris frond that fits the description:

 

Pl_24a.2.thumb.jpg.04dcdb875bce5eb38c3c5d3820be24ea.jpg

 

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Fossil-Hound

Very nice ferns. It's a shame St. Clair is now closed to the public.

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Shamalama
11 hours ago, fiddlehead said:

I agree that the first one is quite a find. And till now unreported as far as I know from the St Clair area. I believe the second one, which was poorly preserved and only appears more interesting than I believe it to be. Based on the lack of even a crease to show any midveins in the pinnules, leads me to believe they did not have any. The only genus which lacks a midvein is Odontopteris. And the only species of Odontopteris reported at St. Clair is O. subcuneata. I don't know that this species is that "common" there but since O. subcuneata is a polymorphic form Macroneuropteris scheuchzerii and it is a common element in this flora, so it should be readily found there. The other features that can be made out also help confirm the taxon. The first one is very rare even where it is known to exist. So much so it is only described on fertile foliage and only one example of sterile foliage is known to exist. It is called Stellatheca ornata and you have a fertile example. A brief description; The ultimate and penultimate rachis appears wide (though partially due to pinnules being slightly confluent) Each pinnule typically has three sori, but can range from two to five, and are placed near the margin. And the pinnules are generally no more than rounded lobes. Attached is a picture of a Mazon Creek example.

 

Hope this helps,

Jack

 

 

Stl.ornPP54627.jpg

 

Jack, Thanks so much for the ID assistance. I looked up pictures for Odontopteris  and it does seem like the second set of pictures matches that.  The Stellatheca ornata is a really cool find and your example looks to be right on the money. The thicker rachis with shallow pinnules really sets it apart from anything else I have found from St. Clair. Even old finds can yield something new!

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