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Brad Warne posted a new specimen in the group What is it? from the myFOSSIL app 3 years, 7 months ago
3 years, 7 months ago3 years, 7 months agoBrad Warne has contributed specimen mFeM 83534 to myFOSSIL!
Brad Warne posted a new specimen in the group What is it? from the myFOSSIL app 3 years, 7 months ago
Brad Warne has contributed specimen mFeM 83534 to myFOSSIL!
Cool
The wider section with the concave ends are remnants of an orthocone (used to be called Orthoceras but thats a wastebasket taxon). Crinoid stems are usually flat, with some features that reveal their 5-pointed radial symmetry and a hole (axial canal) in the center. Not sure about the long thin section. It could be the rest of the orthocone that has weathered into a tiny strip or a crinoid stem that was juxtaposed onto the orthocone. Looking at the end should tell the difference, the orthocone shell should be convex at that end.
Wow. Very interesting. I have an orthocone found from this same creek about thirty years ago.
You’ll notice that I’ve been hacking away at the fossil with a dremel tool to expose most of what you see. I accidentally made a small hole on the section you suggest is an orthocone. The fact that it’s hollow would further suggest the hollow chambers of a cephalopod.
Thank you @patrick-hsieh
But where is the siphuncle in the top down view?
Now that I see it as an orthocone, I think that the long narrow bit is the siphuncle and rest of the cone has broken away.
Yes, I think you’re right! In fact, on page 530 of my copy of Shimer and Shrock’s Index Fossils of North America, (1965 printing), there is a picture of a specimen with the siphuncle and partial camerae preserved just like your specimen.