Greg.Wood Posted January 28, 2018 Share Posted January 28, 2018 All specimens come from the Devonian aged Arkona formation. 1. Echinoderm, possibly a blastoid Tried taking another pic...still not quite sharp 2. Unknown, possibly bryozoans (remainds me a bit of Evactinopora) 3. Unknown, probably the inner structure of ostracods With these being the outer shell: 4. I posted these about a month ago but I don't think we figured it out. Now I am pretty sure they are scaphopods. Link to comment Share on other sites More sharing options...
Al Dente Posted January 28, 2018 Share Posted January 28, 2018 Number two look like crinoid columnals. Link to comment Share on other sites More sharing options...
Greg.Wood Posted January 28, 2018 Author Share Posted January 28, 2018 2 minutes ago, Al Dente said: Number two look like crinoid columnals. Could be, but the shape seems very irregular. Maybe preserved a different way or very worn out. These are the common crinoid bits I'm finding for comparison: Link to comment Share on other sites More sharing options...
Kane Posted January 28, 2018 Share Posted January 28, 2018 The crinoid ossicles usually have a good degree of symmetry, so the second picture in the initial post doesn't quite give me a crinoid columnal vibe. I'll have a look in my literature... They seem to most closely resemble crinoid arm bits. I've seen a few that have that kind of irregular-radial nubs appearance. This is just a best guess based on these pictures, and I'm still uncertain. ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
Darktooth Posted January 28, 2018 Share Posted January 28, 2018 Very interesting items! I like Trilo-butts and I cannot lie. Link to comment Share on other sites More sharing options...
abyssunder Posted January 29, 2018 Share Posted January 29, 2018 I'm pretty sure that the first one (1) is a blastoid calyx, although your pictures are a bit blurry. The second ones (2) have patterns that make me think they might be crinoid columnals, as it was said by Eric really right, according to the central hole which might be the lumen. Try to compare them with the specimens close to yours from the picture below. (It don't has anything related to Evactinopora, I'm affraid.) Nice pictures BTW, thank you for them. The last three ones shows: 1 - columnals, 2 - spines and brachials, 3 - arm fragments, probably of biserial arms. (in my understanding) " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
Shamalama Posted January 29, 2018 Share Posted January 29, 2018 Pic 1 is definitely a Blastoid, not sure of species tho as it is way small. Edit: After another look I want to say Heteroschisma sp. Pic 3 are not Ostracod interiors, they are a different genera and species from those in Pic 4. I think those in Pic 3 are in the family Hollinidae and possibly genus Ctenoloculina (of which there are 5 species listed as known from the Arkona Formation. Attached is a .pdf from the University of Michigan that may help in identifying what you have. Pic 4 might be the ostracod species Ponderodictya punctulifera which is fairly common. Makes me want to go "fishing" again in the screenings I have from Arkona. OSTRACODS OF THE FAMILY HOLLINIDAE FROM THE ARKONA SHALE.pdf -Dave __________________________________________________ Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPheeIf I'm going to drive safely, I can't do geology. - John McPheeCheck out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/ Link to comment Share on other sites More sharing options...
Greg.Wood Posted January 29, 2018 Author Share Posted January 29, 2018 @abyssunder Thanks! I can see the resemblance between #2 on the original post and 8/9/10 on that plate. I'll get a clear shot of the blastoid tonight since the first one didn't turn out. @Shamalama That pdf will be very useful, I'll have to start taking a closer look at these ostracods. I sifted through 4 buckets of mud this winter so I'll have to post everything I found at some point. Link to comment Share on other sites More sharing options...
doushantuo Posted January 29, 2018 Share Posted January 29, 2018 the ostracods might even be useful paleo-ecologically speaking(e.g.presence of Thuringian ecotypes,but also valve ratios,possible presence of instars,velar dimorphism) Link to comment Share on other sites More sharing options...
Packy Posted January 30, 2018 Share Posted January 30, 2018 Attached are some crinoid sections( all photos are 5.5x8.5 mm), which I assume are holdfast sections from the mississippian,and Ordovician similar to yours. very nice finds I will have to visit that area. Packy Link to comment Share on other sites More sharing options...
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