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hitekmastr

Long Slender Vine Or Stem W Elongated Veinless Leaves

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hitekmastr

I can't seem to find an image or plate for this in my fossil books - this is a long branching vine or stem with elongated veinless leaves running along the stems. I've included a full view as well as closeups showing the leaves. The leaves are flat and long and run along the stem in a series.

My impression is that this is a small vine of some sort with leaves running along the stems. It is one of our finds from the Llewellyn Formation at St. Clair.

Any ideas?

Image P8302029a includes arrows pointing to the leaves running along the stems, at the base of the fossil.

Image P8302016a shows the major branching stems - there are also minor stems

Image P8302012a is a closeup of the leaf which appears to have no veins.

Image P8302020a shows another leaf closeup.

Image P8302013a and P8302017a show a closeup of a single leaf.

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post-8709-0-66735900-1346515935_thumb.jpg

post-8709-0-79215100-1346516004_thumb.jpg

post-8709-0-38701400-1346516059_thumb.jpg

post-8709-0-26242400-1346516305_thumb.jpg

post-8709-0-28397600-1346520476_thumb.jpg

Edited by hitekmastr

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Auspex

I wonder it it could be Alethopteris, with the 'stems' being the rib?

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hitekmastr

I wonder it it could be Alethopteris, with the 'stems' being the rib?

Are Alethopteris stems sometimes ribbed with leaflets like this? I've seen similar examples in modern plants where the leaflets run up the stem like this. We found no fern leaves associated with this, anywhere on the fossil sample. If this were Alethoptereris It's an interesting puzzle. Also, there appear to be no veins on the leaves, which also suggests this might be something else. I would have thought there might be some leaves close by but this seemed to be separate. I've read that there were plants from this period and earlier that had only a single central vein and were very primitive and there were also plants that were either very small or were vines...interesting puzzle.

One of the cool things about our plant investigations is that there are still quite a lot of questions unanswered in the fossil record from the Pennsylvanian, so we're intrigued when we turn up something that isn't very clear or obvious since there appears to be a lot to be discovered to fill in the fossil record and that's part of the fun.

Edited by hitekmastr

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Auspex

My thought is that the purported 'stems' in your specimen may in fact be the mid-veins of the fronds. Refer to the image you posted in support of your seed find to see what I mean. :)

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hitekmastr

My thought is that the purported 'stems' in your specimen may in fact be the mid-veins of the fronds. Refer to the image you posted in support of your seed find to see what I mean. :)

Would they line up one after the other if the "stems" were veins? Also, wouldn't there be horizontal veins coming off the central vein - none of the leaves show additional veins although they seem to be articulated well enough that they should show the smaller veins (?).

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Auspex

...Also, wouldn't there be horizontal veins coming off the central vein - none of the leaves show additional veins although they seem to be articulated well enough that they should show the smaller veins (?).

Depends on the preservation; if there is no sign of them, and the preservation is such that you think they should show, then my idea is just a red herring. ;)

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Missourian

It reminds me of crabgrass. :)

Otherwise, I too am scratching my head on that one.

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hitekmastr

It reminds me of crabgrass. :)

Otherwise, I too am scratching my head on that one.

I think the stems are the ribs of the leaves and the leaves SEEM to be arranged one after the other on the same stalk. It does look like crabgrass, but it's like a series of very long leaves that grow on a single rib (or "stem") all in a line - there are some houseplants that look like this, that have all the leaves in a row sharing the same rib (or "stem") - and flat like this. But...is this a separate species like those houseplants, or is it just a variation of something familiar from a different angle or stripped down or whatever? I think because there are several of these all showing the same morphology, they are a kind of branching vine plant that has the leaves lined up on the same vine and the "stem" of the vine also functions as the central rib. I also would venture to suggest that this might be a carryover of one of the more primitive vining plants that are said to exist in previous periods, that could not support themselves to grow upright so they grew as vines - and also, those primitive plants didn't have veins and it appears that the leaves on these "stacked" leaves also don't show any sign of veining.

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hitekmastr

I am not certain on this, but I have always associated what you found with "roots". To what plant they belong I can't be sure; Calamites is my best guess.

I say this because I found the same looking fossils in Paleosols with massive amounts of the "root" or "rhizome" system. I'm talking big like many square

feet of the stuff all intact and connected.

That makes sense, except these look more like very long thin stems with flat elongated leaves arranged one after the other along the stem, without any veins, and where the stem appears to also function as a middle vein. It's almost like a modern creeping vine or some sort with the long leaves arranged right on the stem. The leaves also appear to be segmented and all the same relative size.

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paleoflor

It might be worth looking into the form-genera Pinnularia and Myriophyllites. These represent sphenophyte rootlets.

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hitekmastr

It might be worth looking into the form-genera Pinnularia and Myriophyllites. These represent sphenophyte rootlets.

Great idea - thanks! I hadn't thought of these being rootlets of a fossil vine such as sphenophyte. I've been looking at leaves, stems, bark from St. Clair, and we have a very nice collection of (stigmaria) tree roots - but I had never thought much about the fact that ferns and creeping vines from this period also have roots. Surprising that I hadn't thought much about that so your note is very insightful!!! Nice obervation!

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