minnbuckeye Posted October 26, 2020 Share Posted October 26, 2020 Two weeks ago, I traveled to Central (Devonian) and SE Iowa (Mississippian) for a little fossil hunt. It was very successful and I will complete a trip report soon. In the meantime, it would thrill me to understand a few unknowns from the trip. First of all, the Mississippian, Burlington Formation: 1. and 2. 2. is a brachiopod that I could not find in the lists of brachiopods from the Burlington Formation. 3. There were many of these present in a certain layer of rock. Very circular with longitudinal striations. All roughly an inch in length. 4. Probably my most confusing specimen. It looks just like the little sanddollars I find in Florida. Probably a crinoid piece, but worth the asking!!!! 5. These "trace fossils" were very evident in a certain layer of the Burlington. I am open for suggestions. Now a few Devonian specimens to get your thoughts on. 6. This was found in with many Platyrachella iowensis, a long winged spirifer. This spirifer has SHORT wings. A different species or broken wings?? 7. Finally, I can not find mention of this winged bivalve, Cedar Valley Formation. Thanks for any help you can provide me!!! Mike Sorry!! I forgot a few, all Mississippian. 8. What could the little green discs be that I often find inside the very white crinoidal limestone? 9. This reminds me a bit of a cephalopod but its hollowed out area is on a sharp slant, too much for cephalopod. It does not image well. My apologies. 10. Finally, research pinpoints the fenstrate bryozoan on the left as Hemitrypa. Is the one on the right Archimedes? I am so used to just finding the corkscrew. I promise I am done now! 4 Quote Link to post Share on other sites
Fossildude19 Posted October 26, 2020 Share Posted October 26, 2020 @Jeffrey P @Tidgy's Dad @Shamalama 1 Quote Link to post Share on other sites
Tidgy's Dad Posted October 26, 2020 Share Posted October 26, 2020 Hmmm. Not sure at all. Number 2. Rhipidomella burlingtonensis. 6. Spinocyrtia, I think. 1 Quote Link to post Share on other sites
minnbuckeye Posted October 26, 2020 Author Share Posted October 26, 2020 28 minutes ago, Tidgy's Dad said: Number 2. Rhipidomella burlingtonensis. @Tidgy's Dad, I found other brachiopods that correlate to Rhipidomella burlingtonensis. This one, however, is almost perfectly round. The beak is barely existent. Though the suggestion is the best I could come up with too. Number 6, Spinocyrtia iowensis looks like a winner! 1 Quote Link to post Share on other sites
daves64 Posted October 26, 2020 Share Posted October 26, 2020 I was thinking #6 might be Steven Tyler's lips.. Quote Link to post Share on other sites
Thomas.Dodson Posted October 26, 2020 Share Posted October 26, 2020 #1 kind of looks like a shark denticle but also seems different. Hopefully somebody more knowledgeable about paleozoic denticles will chime in. In my opinion #7 definitely belongs in family Pterineidae (Miller 1877). There are multiple genera it could belong to but I'm not familiar with them or the Cedar Valley Formation so I can't say which. Hopefully this helps narrow your search. Quote Link to post Share on other sites
minnbuckeye Posted October 26, 2020 Author Share Posted October 26, 2020 36 minutes ago, Thomas.Dodson said: #1 kind of looks like a shark denticle but also seems different. Hopefully somebody more knowledgeable about paleozoic denticles will chime in. In my opinion #7 definitely belongs in family Pterineidae (Miller 1877). There are multiple genera it could belong to but I'm not familiar with them all so I can't or Cedar Valley Formation so I can't say which. Hopefully this helps narrow your search. @Thomas.Dodson,I was fortunate to find some great shark material in the Burlington. It will be shown in my trip report. The material is very dark, I would say black. If this was darker colored, I would up the odds of a denticle, but...... Could the denticle be gone leaving only an imprint? " #7 definitely belongs in family Pterineidae". That is great for beginning further research! Thanks. Quote Link to post Share on other sites
minnbuckeye Posted October 27, 2020 Author Share Posted October 27, 2020 @Elasmohunter, thought I would message you for your thoughts. I know you have been involved with the Burlington limestone. Quote Link to post Share on other sites
hemipristis Posted October 28, 2020 Share Posted October 28, 2020 Very nice preservation in the first couple! Quote Link to post Share on other sites
Elasmohunter Posted October 29, 2020 Share Posted October 29, 2020 Sorry for being late to the party! I need to adjust my notification settings. . . . 1) I do not believe that it's is a denticle, as all vertebrate material that I've seen from the Burlington and Keokuk Limestones is black, and it doesn't look like a denticle. To the contrary, the white fossils are usually calcitic invertebrates, so it's probably invert. Could it be a coral of sorts? 2) My thesis has a list of brachiopods reported from the Burlington that might be of use. 3) This is a rock structure often found within limestones called a stylolite. These are common in the Burlington Limestone. https://en.wikipedia.org/wiki/Stylolite 4) A fragment of a crinoid calyx/a crinoid plate? Out of my area of expertise. . . . 8) This is likely a fleck of glauconite, which forms in marine environments and often occurs in great concentrations during times of decreased sedimentation rates. Some layers of the type Osagean have so much of this mineral that the limestone appears almost greenish. 9) No idea. I'm not even sure if it's a fossil or not; it's a little tough to tell. I can't provide you with any help on 5, 6, 7, or 10. Hope this helps! Quote Link to post Share on other sites
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