Mazon Creek ID help

[Mark Kmiecik]

Calling on the usual suspects, @stats @deutscheben @bigred97 @Nimravis @fiddlehead @flipper559 @connorp @RCFossils , to either confirm or refute my meager guesses at ID on these ferns. Thank you all in advance -- I truly appreciate your help. And of course, I'll consider what any others think as well. Thank you.

 

   

 

  

Edited March 1, 2022 by Mark Kmiecik
adjust photo

[Nimravis]

I will let the others chime in on this, they are all Pecopteris to me. Lol

[Mark Kmiecik]

31 minutes ago, Nimravis said:

I will let the others chime in on this, they are all Pecopteris to me. Lol

 

Yeah, same problem. Although I'm remembering the new names, I still can't link the name to the specimen, with the possible exception of Diplazites unita. I think I may have that one down. Thanks for taking a look.

 

I've got some more interesting ones coming up in the next batch.

Edited March 1, 2022 by Mark Kmiecik

[connorp]

I'd agree that the last three are probably C. acadica. The first might be another species of Crenulopteris. C. acadica has around ten lobes per pinnule, this one has less. If I had to pick one, I'd say C. mazoniana, but I'm still not very comfortable with that species. The second does not look like Diplazites to me. In particular, the pinnules are completely separated and not united. Can you make out the venation? D. unita has simple lateral veins (i.e. unforked) that arc towards the pinnule apex.

[Mark Kmiecik]

13 hours ago, connorp said:

I'd agree that the last three are probably C. acadica. The first might be another species of Crenulopteris. C. acadica has around ten lobes per pinnule, this one has less. If I had to pick one, I'd say C. mazoniana, but I'm still not very comfortable with that species. The second does not look like Diplazites to me. In particular, the pinnules are completely separated and not united. Can you make out the venation? D. unita has simple lateral veins (i.e. unforked) that arc towards the pinnule apex.

 

Thanks for chiming in. I appreciate your input very much, as I am even less comfortable with all of them, let alone C. mazoniana. I labeled the second one ?D. unita because the pinnules are united from halfway up the pinna to the tip and many are united towards the base. I originally had it labeled Pecopteris mazoniana. I keep reading and re-reading Jack's book and I just get more confused each time I do. Other than the drawings I'm not getting the comparative info I need to get it all straight in my head. I wish someone would create a chart that shows each species venation, etc. so I could compare a specimen to it and make a reasonably correct ID. I did not even suspect the first one of being C. mazoniana.

[connorp]

15 minutes ago, Mark Kmiecik said:

 

Thanks for chiming in. I appreciate your input very much, as I am even less comfortable with all of them, let alone C. mazoniana. I labeled the second one ?D. unita because the pinnules are united from halfway up the pinna to the tip and many are united towards the base. I originally had it labeled Pecopteris mazoniana. I keep reading and re-reading Jack's book and I just get more confused each time I do. Other than the drawings I'm not getting the comparative info I need to get it all straight in my head. I wish someone would create a chart that shows each species venation, etc. so I could compare a specimen to it and make a reasonably correct ID. I did not even suspect the first one of being C. mazoniana.

I've read the book many times through myself. Lot's to digest, and I'm still learning more everyday. Here is a helpful diagram to understand some of the terminology used to discuss pecopterid pinnules. I don't remember exactly where I found it, I think it is a page from one of the Langford books.

 

Another very helpful resource is the Field Museum Collections database. There are lots of images to view, especially for true ferns (not many of seed ferns unfortunately).

https://collections-geology.fieldmuseum.org/list