Rockpit Posted August 6, 2018 Share Posted August 6, 2018 I collected some small nodules last week and when I tried to open this one the top split to reveal this. I decided to hit the larger part one more time to see if I could uncover the rest. Instead the larger piece split in half and this is what was inside the same nodule. Are these annularia? They are very different from the other fossil I found in the right picture which I am pretty sure is annularia. Link to comment Share on other sites More sharing options...
Rockpit Posted August 6, 2018 Author Share Posted August 6, 2018 I found these halves covered in too much dirt to tell if there was anything inside. I was happy to find this little leaf. I also found this as is. Link to comment Share on other sites More sharing options...
lawooten Posted August 6, 2018 Share Posted August 6, 2018 I love nodules! You never know what you will get when u cut them open. Wish we had them in NC The best days are spent collecting fossils Link to comment Share on other sites More sharing options...
Rockpit Posted August 9, 2018 Author Share Posted August 9, 2018 I agree. It is exciting when something is actually inside one. I just can't always figure out what that something is! Link to comment Share on other sites More sharing options...
deutscheben Posted August 9, 2018 Share Posted August 9, 2018 On 8/5/2018 at 10:13 PM, Rockpit said: I collected some small nodules last week and when I tried to open this one the top split to reveal this. I decided to hit the larger part one more time to see if I could uncover the rest. Instead the larger piece split in half and this is what was inside the same nodule. Are these annularia? They are very different from the other fossil I found in the right picture which I am pretty sure is annularia. That does looks like an Annularia, but a different species than your second specimen. The thin-leaved one is A. radiata while the other find is A. stellata. See this page: https://paleobiology.si.edu/mazoncreek/mazonSphenopsida.html for some good examples. Link to comment Share on other sites More sharing options...
KimTexan Posted August 9, 2018 Share Posted August 9, 2018 I am no pro on these, but # 2 pic look like some leaves are flat tipped to me. Are the leaves triangular? Are the ends of the leaves flat or rounded? Annularia are rounded I believe and Sphenophyllum is flat tip. Sometimes it is hard to tell things via pics. Here is a very good description of how to tell the difference between the 3 types of Calamities: Annularia, Asterophyllites and Sphenophyllum. Its a very useful site. https://samnoblemuseum.ou.edu/common-fossils-of-oklahoma/plant-fossils/fossils-by-plant-group/fossil-sphenophytes/ Link to comment Share on other sites More sharing options...
paleoflor Posted August 9, 2018 Share Posted August 9, 2018 To separate Sphenophyllum from Annularia and Asterophyllites, I would rather look at the venation of the leaflets. In both Annularia and Asterophyllites each leaflet in the whorl has only a single midvein. By contrast, Sphenophyllum leaflets typically have multiple or dichotomising veins. The shape of the leaflets is much more variable, making it less reliable as diagnostic tool. In the case of Sphenophyllum, leaflet shape is known to even vary significantly within species. Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
minnbuckeye Posted August 9, 2018 Share Posted August 9, 2018 Here is a very good description of how to tell the difference between the 3 types of Calamities: Annularia, Asterophyllites and Sphenophyllum. Its a very useful site. @KimTexan, love the link! It helped me ID a few leaves that I own. @sixgill pete, on one of those fern plates I sent, I think there is Sphenophyllum present. At least my guess since the fossil is in the mail. Link to comment Share on other sites More sharing options...
KimTexan Posted August 9, 2018 Share Posted August 9, 2018 11 hours ago, paleoflor said: To separate Sphenophyllum from Annularia and Asterophyllites, I would rather look at the venation of the leaflets. In both Annularia and Asterophyllites each leaflet in the whorl has only a single midvein. By contrast, Sphenophyllum leaflets typically have multiple or dichotomising veins. The shape of the leaflets is much more variable, making it less reliable as diagnostic tool. In the case of Sphenophyllum, leaflet shape is known to even vary significantly within species. Yes that info was in the link I provided and then some. Link to comment Share on other sites More sharing options...
KimTexan Posted August 9, 2018 Share Posted August 9, 2018 7 hours ago, minnbuckeye said: Here is a very good description of how to tell the difference between the 3 types of Calamities: Annularia, Asterophyllites and Sphenophyllum. Its a very useful site. @KimTexan, love the link! It helped me ID a few leaves that I own. @sixgill pete, on one of those fern plates I sent, I think there is Sphenophyllum present. At least my guess since the fossil is in the mail. I use that site fairly often when it comes to carboniferous plant ID. They have a huge database. Not all specimens have pics, but there are still many that do. There’s lots of helpful info there. Link to comment Share on other sites More sharing options...
paleoflor Posted August 10, 2018 Share Posted August 10, 2018 12 hours ago, KimTexan said: Yes that info was in the link I provided and then some. Checked your link. Very useful indeed. I initially only focussed on what you wrote about leaflet shape above your link, sorry. Of the several pointers (retrospectively) provided via your link, I feel venation is the more robust characteristic. The leaflet shape becomes more variable and less reliable to use when you consider the species level. Annularia sphenophylloides, for example, is a species of Annularia with leaflets resembling Sphenophyllum. Searching for green in the dark grey. Link to comment Share on other sites More sharing options...
KimTexan Posted August 10, 2018 Share Posted August 10, 2018 3 hours ago, paleoflor said: Checked your link. Very useful indeed. I initially only focussed on what you wrote about leaflet shape above your link, sorry. Of the several pointers (retrospectively) provided via your link, I feel venation is the more robust characteristic. The leaflet shape becomes more variable and less reliable to use when you consider the species level. Annularia sphenophylloides, for example, is a species of Annularia with leaflets resembling Sphenophyllum. I agree. In photos though it is often difficult to see the veins so I default to the shapes I can see, but even those aren’t always clear. When in question I provide the link for people. Link to comment Share on other sites More sharing options...
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