Peat Burns Posted March 14, 2017 Share Posted March 14, 2017 Hi All, I am hoping someone might recognize this bone fragment. It is from the Hell Creek Formation (Late-Cretaceous) of South Dakota. It looks fishy to me but does not have the exterior texture of gar skull. The exterior is really "pocked", almost like small, conchoidal chips. If fish, maybe bowfin, paddlefish, or sturgeon skull fragment? Only other thought I had was maybe crocodilian or champsosaur skull fragment, but I am leaning fish. There might be enough structure on the interior surface for someone to recognize which bone. Top photo is the exterior surface, middle is interior surface, and bottom photo is close-up (under magnification) of the exterior surface. Scale is in cm / mm. Thanks for any help. Link to comment Share on other sites More sharing options...
Troodon Posted March 14, 2017 Share Posted March 14, 2017 Far from an expert first thing that structure me was Sturgeon plate 1 Link to comment Share on other sites More sharing options...
PFOOLEY Posted March 14, 2017 Share Posted March 14, 2017 @Peat Burns, could you post some closeups? EDIT: images that can be individually viewed at full size. 1 "I am glad I shall never be young without wild country to be young in. Of what avail are forty freedoms without a blank spot on the map?" ~Aldo Leopold (1887-1948) New Mexico Museum of Natural History Bulletins Link to comment Share on other sites More sharing options...
PFOOLEY Posted March 14, 2017 Share Posted March 14, 2017 How thick is the specimen?...leaning towards turtle. "I am glad I shall never be young without wild country to be young in. Of what avail are forty freedoms without a blank spot on the map?" ~Aldo Leopold (1887-1948) New Mexico Museum of Natural History Bulletins Link to comment Share on other sites More sharing options...
Peat Burns Posted March 14, 2017 Author Share Posted March 14, 2017 17 minutes ago, PFOOLEY said: How thick is the specimen?...leaning towards turtle. It's about 3-4 mm thick (sorry, I should have included that) Link to comment Share on other sites More sharing options...
Peat Burns Posted March 14, 2017 Author Share Posted March 14, 2017 39 minutes ago, PFOOLEY said: @Peat Burns, could you post some closeups? EDIT: images that can be individually viewed at full size. I'll post some better close-ups tonight, including side-view (I'm away from my work area at the moment). Link to comment Share on other sites More sharing options...
Al Dente Posted March 14, 2017 Share Posted March 14, 2017 I agree with turtle. Looks like a neural bone. 1 Link to comment Share on other sites More sharing options...
jpc Posted March 14, 2017 Share Posted March 14, 2017 as long as you are going to post a few more pix, can we see a photo of the broken edge. Link to comment Share on other sites More sharing options...
Peat Burns Posted March 14, 2017 Author Share Posted March 14, 2017 12 minutes ago, jpc said: as long as you are going to post a few more pix, can we see a photo of the broken edge. Yes. It will be helpful, I think. It tapers off to a thin edge rather than being a 90 degree fracture typical of most of the turtle shells I find. I should be able to post something by 9 pm EST. Link to comment Share on other sites More sharing options...
Peat Burns Posted March 15, 2017 Author Share Posted March 15, 2017 @Al Dente, @jpc, @PFOOLEY, @Troodon, et al. This may take several replies. These two pics are photos of the edge of the fossil (see caption on photos for details) The pic below is a close-up of the "pocked" dorsal surface texture (i.e. not a regular pattern as in typical turtle shell) Link to comment Share on other sites More sharing options...
Peat Burns Posted March 15, 2017 Author Share Posted March 15, 2017 @Al Dente, @jpc, @PFOOLEY, @Troodon, et al. This shows the fossil in question (left) next to a Hell Creek turtle pleural and neural in both oblique and ventral views (see notes on photo) This photo shows the edge of a Hell Creek turtle pleural of similar thickness to the fossil in question (above) and a Hell Creek turtle Neural below. Link to comment Share on other sites More sharing options...
Peat Burns Posted March 15, 2017 Author Share Posted March 15, 2017 Another macro view of the ventral side showing unusual texture. Link to comment Share on other sites More sharing options...
PFOOLEY Posted March 15, 2017 Share Posted March 15, 2017 I will stick with turtle. I believe it is the weathering of the piece that is creating the unusual features. 1 "I am glad I shall never be young without wild country to be young in. Of what avail are forty freedoms without a blank spot on the map?" ~Aldo Leopold (1887-1948) New Mexico Museum of Natural History Bulletins Link to comment Share on other sites More sharing options...
Peat Burns Posted March 15, 2017 Author Share Posted March 15, 2017 Just now, PFOOLEY said: I will stick with turtle. I believe it is the weathering of the piece that is creating the unusual features. Thanks very much. Do you think the depression / concavity is where the spinal encasement eroded away (i.e. a neural)? Link to comment Share on other sites More sharing options...
jpc Posted March 15, 2017 Share Posted March 15, 2017 turtle. Remember, there are many types of turtles in the Hell Creek and each turtle has many different neural bones,and they come in thicknesses. 3 Link to comment Share on other sites More sharing options...
PFOOLEY Posted March 15, 2017 Share Posted March 15, 2017 5 minutes ago, Peat Burns said: Thanks very much... You are welcome. 5 minutes ago, Peat Burns said: ...Do you think the depression / concavity is where the spinal encasement eroded away (i.e. a neural)? Yes. 1 "I am glad I shall never be young without wild country to be young in. Of what avail are forty freedoms without a blank spot on the map?" ~Aldo Leopold (1887-1948) New Mexico Museum of Natural History Bulletins Link to comment Share on other sites More sharing options...
Boesse Posted March 16, 2017 Share Posted March 16, 2017 One more onto the turtle bandwagon. This isn't really a good match for sturgeon. Sturgeon bone ornamentation (regardless of the genus...) pretty much resembles this: 1 Link to comment Share on other sites More sharing options...
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