connorp Posted February 14, 2020 Share Posted February 14, 2020 Going through last year's finds I found a few things that I don't recognize. All are from Pennsylvanian marine limestone. The first few all appear to be fish material of some kind. I find plenty of chondrichthyan teeth, but none of these look like any teeth I've seen, although they may be partials. Possibly some kind of bony fish scale? All images were taken under a microscope, no scale cube but they all are about 1/2" at the widest point. #1) #2) 1 Link to comment Share on other sites More sharing options...
connorp Posted February 14, 2020 Author Share Posted February 14, 2020 #3) And #4 appears to a gastropod. It was on a block of matrix with a tooth that was in a vinegar bath, and I only noticed it after a few hours in the bath. So I'm guessing there's not enough detail for an ID, but was hoping it was possible to narrow it down, maybe even just to family or order. Not very impressive, but it's the only gastropod I've ever found at this site. #4) 3 Link to comment Share on other sites More sharing options...
Fossildude19 Posted February 14, 2020 Share Posted February 14, 2020 @jdp Looks like paleoniscoid skull elements and possible scales. Something like Haplolepis sp possibly? Can't help with the gastropod cross section. Great finds, in my opinion. Thanks for posting these. EDIT: Have a look at this post. 9 Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
connorp Posted February 15, 2020 Author Share Posted February 15, 2020 14 hours ago, Fossildude19 said: @jdp Looks like paleoniscoid skull elements and possible scales. Something like Haplolepis sp possibly? Can't help with the gastropod cross section. Great finds, in my opinion. Thanks for posting these. That seems likely, not sure where else thick bony elements would come from. Are the holes in the elements anything specific to paleoniscids? They are present in all the specimens I showed, I've also seen similar holes in microfossils from the Pennsylvanian black shales I've searched, like the one below. Link to comment Share on other sites More sharing options...
Fossildude19 Posted February 15, 2020 Share Posted February 15, 2020 5 hours ago, connorp said: That seems likely, not sure where else thick bony elements would come from. Are the holes in the elements anything specific to paleoniscids? They are present in all the specimens I showed, I've also seen similar holes in microfossils from the Pennsylvanian black shales I've searched, like the one below. Well, the sheen from the black "holey" elements are very indicative of fish scales/bone/skull elements. Not sure if the holes are specific to paleoniscoid fish. It could be that they are artifacts of erosion of thinner parts of the scales/bones. Some holes seem to indicate areas of interlocking components. I know that the ornamentation on paleoniscoid fish can vary greatly. These elements seem more bone like, to me. Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
jdp Posted February 17, 2020 Share Posted February 17, 2020 Yep, most of those are fragments of fish bone. Not really clear to me what type of fish, but haplolepids are overwhelmingly freshwater so it's probably not a haplolepid. 2 Link to comment Share on other sites More sharing options...
jdp Posted February 17, 2020 Share Posted February 17, 2020 On 2/15/2020 at 6:05 AM, Fossildude19 said: Well, the sheen from the black "holey" elements are very indicative of fish scales/bone/skull elements. Not sure if the holes are specific to paleoniscoid fish. It could be that they are artifacts of erosion of thinner parts of the scales/bones. Some holes seem to indicate areas of interlocking components. I know that the ornamentation on paleoniscoid fish can vary greatly. These elements seem more bone like, to me. That larger element is a piece of the braincase of an actinopterygian fish, absolutely. The circle looks like a specific type of exposure of the common dorsal aorta you see in a variety of Carboniferous and Permian actinopts, including things like Coccocephalus and Leuderia. There's enough there that it might be diagnosable to a broader taxonomic group. You actually have an expert on Palaeozoic fishes right by you in Mighican; try sending some pics to Matt Friedman at UMich and see what he thinks. This specimen might be scientifically useful, so I'd try getting in touch with him. 4 Link to comment Share on other sites More sharing options...
connorp Posted February 17, 2020 Author Share Posted February 17, 2020 1 hour ago, jdp said: That larger element is a piece of the braincase of an actinopterygian fish, absolutely. The circle looks like a specific type of exposure of the common dorsal aorta you see in a variety of Carboniferous and Permian actinopts, including things like Coccocephalus and Leuderia. There's enough there that it might be diagnosable to a broader taxonomic group. You actually have an expert on Palaeozoic fishes right by you in Mighican; try sending some pics to Matt Friedman at UMich and see what he thinks. This specimen might be scientifically useful, so I'd try getting in touch with him. I have a meeting in his department Thursday, I'll try to see if he's available then. Thanks! 1 Link to comment Share on other sites More sharing options...
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