Alethopteris sp?

[Strepsodus]

I recently obtained this plant fossil in a trade.  It comes from the Kent coal measures (UK), upper Carboniferous.  I suspect it is Alethopteris sp, though the pinnules are smaller than any species of Alethopteris I can find.  Any ideas what it may be?
Thanks,

Daniel

[Archie]

It does look like an Alethopteris sp., fantastic piece!

[Kato]

20 minutes ago, Archie said:

It does look like an Alethopteris sp., fantastic piece!

It is a nice specimen. Would love to see a zoom into some of the pinnules.

[nala]

Very nice,i think it could be  a Pecopteris (senftenbergia )plumosa dentata Brongniart ,this is a picture from Bruno Valois,a french collector

[Rockwood]

It should be noted that both observations are correct, and likely are not the only examples that could be suggested. Careful study of multiple characters is needed to confidently identify such a specimen. 

[Strepsodus]

Thanks for the replies.  Unfortunately, the vein detail is not present, though it is certainly one of the best plant fossils in my collection.

[nala]

TThe sample from the Paris museum with the id  

[nala]

My personnal samples from France

[Rockwood]

What features are you arguing distinguish the original post from Alethopteris sp ?

[nala]

This is two kind of Alethopteris,it's easy to see the difference 

Alethopteris decurrens (ARTIS) ZEILLER, 1886

[nala]

[nala]

[Rockwood]

1 hour ago, nala said:

This is two kind of Alethopteris,it's easy to see the difference 

Yes. In your examples I agree.

I guess the only thing I can say is, in regard to the post, I respectfully disagree. 

[paleoflor]

The small size of the pinnules does not fit well with Alethopteris. Some of the pinnules seem to have somewhat undulating lateral margins, also does not fit well with Alethopteris. I would agree with nala that this more likely is some pecopterid.

[Strepsodus]

Thanks for the replies.  Pecopterids do seem more common in the Kent coal field than most other coal fields of Britain, so Pecopterid would make sense.  I do occasionally find them in the Yorkshire coal field though not very often.

[Rockwood]

47 minutes ago, paleoflor said:

The small size of the pinnules does not fit well with Alethopteris. Some of the pinnules seem to have somewhat undulating lateral margins, also does not fit well with Alethopteris. I would agree with nala that this more likely is some pecopterid.

An ounce of why is worth a pound of what to me.

[FossilDAWG]

Paleoflor always provides excellent informative responses with discussion of diagnostic characters.

 

Don

[Mark Kmiecik]

It's Alethopteris. 

 

[westcoast]

2 hours ago, Mark Kmiecik said:

It's Alethopteris. 

 

My understanding is that it's not quite as straightforward as this. Both alethopteris and pecopteris can have confluent pinnule bases...

[Mark Kmiecik]

7 minutes ago, westcoast said:

My understanding is that it's not quite as straightforward as this. Both alethopteris and pecopteris can have confluent pinnule bases...

My understanding has always been that was the way to differentiate the two of them. Of course, I have been wrong on many occasions so I did some research and have found examples of both having both configurations and am now thoroughly confused.

[westcoast]

7 hours ago, Mark Kmiecik said:

My understanding has always been that was the way to differentiate the two of them. Of course, I have been wrong on many occasions so I did some research and have found examples of both having both configurations and am now thoroughly confused.

Likewise. 

[Rockwood]

On 12/29/2019 at 3:15 PM, Rockwood said:

Careful study of multiple characters is needed to confidently identify such a specimen. 

The next best thing is the opinion of those who have such experience. 

I just finished rereading Cleal and Thomas's Introduction to Plant Fossils so I had a good sense of the difficulties.

[nala]

In fact,when you saw a lot of samples,it's very easy to see what is a Alethopteris,Neuropteris,Mariopteris,Eusphenopteris,Pecopteris,Lonchopteris.Inside those ,it's really difficult to say