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  1. SharkySarah

    Turrisaspis elektor armor

    From the album: Devonian, Catskill Fm., Pennsylvania USA

    Placoderm armor
  2. SharkySarah

    Turrisaspis elektor armor

    From the album: Devonian, Catskill Fm., Pennsylvania USA

    Placoderm armor
  3. SharkySarah

    T. elektor median dorsal plate

    From the album: Devonian, Catskill Fm., Pennsylvania USA

    Trunk fragment of Turrisaspis elektor placoderm
  4. Misha

    Wudinolepis weni

    Wudinolepis weni, tiny Microbrachiid placoderms from the early Devonian Jiucheng Fm. In Yunnan China. Specimens measure just over 1 cm in length, 2 are present on this piece, one exposed dorsally and the other ventrally. Preparation done by Paul Freitag
  5. bockryan

    Placodermi

    From the album: Fossil Collection: DC Area and Beyond

    Placodermi Capon Lake, WV Needmore Formation (Hares Valley Member) Early Devonian *Donated
  6. bockryan

    Turrisaspis elektor

    From the album: Fossil Collection: DC Area and Beyond

    Turrisaspis elektor Red Hill Fossil Site, PA Catskill Group Late Devonian
  7. From the album: Lower Devonian fossils

    Wudinolepis weni Tiny Microbrachiid antiarch placoderms Late Emsian Lower Devonian Jiucheng Formation Wuding, Yunnan, China. Two specimens are present on the plate, one exposed ventrally (left) one dorsally (right) Prepared by Paul Freitag of Freitag Fossils
  8. I have been meaning to do this for over a year. So this is going to be a bit piecemeal. Me and my son Ian have been collecting in the Catskill formation for 14 years now! In June we made a very quick trip to Red Hill and then to Rt 15. Red Hill as anyone who has recently been there has become a difficult site to find anything new at. Decades of excavation have removed most of the easy material. Our goal has always been to add more fossil evidence to the fragmentary tetrapod remains found so far and in 2021, I thought we had found what I thought could only be a tetrapod shoulder girdle although not well preserved. Unfortunately, when I sent it to the Academy of Natural Sciences in Philly, Ted Daeschler was unable to make any call on it and so it sits in some drawer there. So in 2022 while at Red Hill with Ian on another hot day we decided to take a walk on the railroad tracks. The access is not easy and it's a pretty long hike any way you go. What we found was lag material at the base of the cliff. Probably a flood event that swept a large number of fish (parts) into a very small depression where they were covered. Most of the material is fragmentary Megalichthys mullisoni. There is some placoderm and acanthodian fragments but the next most common fossil is sarcopterygian, probably Hyneria and a mystery sarcopterygian which shows up pretty much throughout the Catskill fm. We went back in June this year and this time brought climbing gear to find and see if we could loosen material from the layer. Turns out the productive layer was just below the lip of the cliff and we were able to drop a bunch of material down to the bottom where amongst a lot of interesting fragments was a posterior jaw fragment. The jaw was fairly low and thick, a large adductor fossa, had no ornament we could make out but a very faint radiating pattern, no cosmine but we could make out a series of fenestra along the Meckelian cartilage. Finally there are four broke teeth (fangs?) of the last (3rd) coranoid and a small empty shelf laterally where presumably the posterior portion of the dentary would sit. All this has led me to believe this is a fragment of Densignathus rowei especially the multiple teeth in the middle of the jaw. I've sent images (multiple times) to Ted and Jason Downs at ANSP but haven't gotten a definite answer. This specimen will eventually be sent down to them but seeing if truly Densignathus, it is not anything new. Still, pretty cool! Lateral view. Clearly no cosmine and no obvious ornament. There is a very weak radiating pattern on the angular. Lingual view Dorsal view. Coronoid " fangs" are the ridge in the middle on the left side. Lateral side is top and you can see the little shelf for the dentary. The adductor fossa takes up most of the right side and the articulation site on the right is broken off. Daeschler, J. Paleont., 74(2), 2000, pp. 301–308 More to come soon!
  9. Our fossil shed is finally done, with the last work of the carpenter to install a door and the last bits of insulation. So now it is time to clean up the place and reorganise a little. This weekend I took a selection of my best material out from the Lompret quarry in Belgium and started to reorganise it. Most of it are Gephuroceratidea goniatites like Manticoceras sp. And Crickites sp. , but also some Oncoceridea, Orthocones, crinoids, placoderm and more. I’ll be taking more pictures this week when I keep on filling the cabinets. pics on both sides from the 1st table: 2nd table: time to fill up the cabinets: The Manticoceras sp. cabinet: ( close up's will follow )
  10. Paul1719

    Turrisaspis elektor

    Very common placoderm at Red Hill site, but rarely articulated. Diagnosis. A small groenlandaspidid with a short head shield and tall and narrow dorsal trunk elements. The head shield is almost as wide as long (average W/L equals 0.96). The pineal is divided into two distinct plates in every specimen and the postmarginal makes contact with the postorbital plate, excluding the marginal plate from the lateral margin of the head shield. A continuation of the supraorbital sensory line reaches the caudal margin of the paranuchal plate. The PDL has an average H/L ratio of 2.42. The posterodorsal projection of the PDL is short and angled sharply upward so that the overlap zone for the MD does not reach the caudal margin of the element. The height of the symphysial area on the visceral surface of the PDL is 40% of the total height of the element. The MD is also high and narrow and approximately equal in height to the PDL. The MD has numerous coarse serrations along the caudal margin and tubercles on the lateral surfaces that form rows parallel to the ventral margin. ADL, anterior dorsolateral plate; AL, anterior lateral plate; AMV, anterior median ventral plate; APi, anterior pineal plate; AVL, anterior ventrolateral plate; Ce, central plate; IL, interolateral plate; M, marginal plate; MD, median dorsal plate; Nu, nuchal plate; PDL, posterior dorsolateral plate; Pi, pineal plate; PL, posterior lateral plate; PM, postmarginal plate; PMV, posterior median ventral plate; PNu, paranuchal plate; PPi, posterior pineal plate; PrO, preorbital plate; Psp, parasphenoid; PtO, postorbital plate; PVL, posterior ventrolateral plate; R, rostral plate; Sgn, supragnathal; SP, spinal plate. EDWARD B. DAESCHLER,1* ANNA C. FRUMES2 AND C. FREDERICK MULLISON1 Records of the Australian Museum (2003) Vol. 55: 45–60. ISSN 0067-1975
  11. Hi all, I thought this specimen was worth posting! This placoderm from the Taemas/Wee Jasper area of southern NSW has beautifully intricate internal preservation. Not certain what the hollow structures are but perhaps they're blood vessels? It was acid prepped it quite a few years ago when I was far less experienced (not that I'm that experienced now), so I'm surprised it came out this well. Edit: John Long said as follows, "Looks like a buchanosteid left rear part of braincase with spinal nerves enclosed in perichondral bone tubes" This paper provides some context on the fossils from the area. The fish fossils from here are renowned for their intricate preservation! LINK Excuse the patchy ammonium chloride application, these photos took a long time to process so I dread redoing them.
  12. Going through material from last year and found this piece. It looks to be some sort of plates. Roughly 1.5"×1" for full specimen. Larger plates are around 1.25cm in diameter with the smaller ones around 2/3 cm. I don't recognize it. I tried the lick test as I was told bone sticks to your tongue and it does stick. Fish plates have been found in this locality but I have never found anything definitive. Unsure of the formation. It was near the bell shale washout in Rockport quarry where I picked it up. I suspect it came off the hill going west of the creek near the trail.
  13. A few months ago I started to prepare this specimen which we collected five or so years ago near Wee Jasper, NSW. Specimens from this site must be acid prepared since they are encased in a hard limestone, making mechanical preparation impossible. Included will be my method for preparing this specimen, as well as my mistakes! Placoderm fossils from this site are typically found as black cross sections, just like the pictured specimen. Bone can be distinguished from other fossils in most cases due to the bumpy texture present on the exterior surface. To consolidate the specimen before working on it, I applied very dilute paraloid-b72 to the bone. At this stage, a dilute solution is best to ensure the paraloid can penetrate as deep into the bone as possible. If the ratio of paraloid to acetone is too high, the solution will be too viscous and the paraloid will only coat the surface of the bone. Next, I air scribed the bulk of the matrix I wanted to remove in order to greatly speed up the process. Here is the specimen after a couple of baths in 8% acetic acid (double strength store bought vinegar): Between acid baths, I let the specimen soak in water for a couple of days to remove any residual vinegar and prevent the build up of crystals which may form inside the bone and damage it once it dries out. Once dry, I applied more of the dilute paraloid to the freshly exposed bone with an eye dropper, making sure the bone was soaked and well consolidated. A photo showing matrix carefully removed with an air scribe between acid baths: I think it was around this point I made a very annoying and easily preventable mistake - I broke the fossil while moving it. It was easy to glue the pieces back on with a stronger, more viscous solution of 20% paraloid but now there are some ugly cracks through the specimen in places. I opted for paraloid instead of superglue because it is easily removable, if I'm not satisfied with my reattachment I just have to apply some acetone and the glue will dissolve again. I broke a couple of other pieces off too which is incredibly annoying, fragile fossils and I don't tend to mix well! Here are some photos of the finished specimen: Note the cracks on the right side of the specimen in this photo. I can't remember how I broke so much off at one time but it is incredibly annoying and so easily avoidable! The fracture towards the left side of the specimen here is natural, it may have been filled in by a band of silica which makes up much of the remaining rock. The crack in this photo was a natural fracture, but it looks like a larger chunk of bone fell off when I was gluing it back together before I started the acid preparation. This photo was taken at almost same angle as the "before" photo below it for reference! Here it is easy to see where the blueish limestone dissolved away, leaving only the bone and the bands of silica which make a convenient stand and support for the fossil. Thank you for reading:)
  14. Mahnmut

    Placoderm from Latvia

    Hello dear fellow forum members, some years ago I acquired some cheap shards of supposed placoderm armor from one of the baltic states, Latvia I think, and thats sadly all the infomation i got. I just found the time to take a closer look at them and think that the three biggest parts seem to fit together, the rest is crumbs. Is there anyone who can tell me more about what I have here, genus, family, anatomy... Thanks J
  15. Last wekend Natalie and I had a quick little field trip to my favorite quarry in southern Belgium. The prospecting was done in the rain, but it cleaned of the dust of the sree piles, so we did find some decent stuf. Most of it were goniatites, but Natalie also found a nice orthocone and we did find quite a few placoderm remains. Natalie found this nice loose Manticoceras, just a little chemical preparation and the air scribe to clear out the center: The orthocone she found, after the prepp: One of the Manticoceras I found was a lot harder to prep: a fragment of a median dorsal plate from a large arthrodire placoderm: And a little nodule with a very well preserved bone fragment, It turned out to be the posterior part of an infragnathal
  16. Misha

    Arthrodire placoderm bone

    From the album: Misha's Late Devonian Fossils

    Arthrodire placoderm bone Unknown species Found near the boundary of the marine Catskill and Lock Haven Fms in light gray colored sandstone Unfortunately the bone was very weathered and fell apart while splitting down the matrix, this is what I was able to piece back together. Lock Haven Formation Frasnian-Fammenian Pennsylvania
  17. At the “Dig with the Experts” earlier this month at Penn Dixie, I found this interesting surface fossil on a block that the on location experts seemed to agree was a placoderm fossil. Approximately 5 inches (12.5cm), it is thin, pigmented and has intermittent perforations or pustules. In an adjacent pile, another more extensive and remarkable set of fossil strips like this presumptive placoderm were found by another rock buster. Anecdotally, it was remarked by staff that these two putative placoderm blocks were excavated from the “same region” of the pit as the apparent Dunkleosteus jaw discovery. Perhaps just a coincidence, but nonetheless an interesting mystery.
  18. Hello! I got back from some travels to Turkey (no fossil hunting there this time, I did however have some nice fossil gifts from the US I was bringing to my relatives seized by Turkish customs which was... fun) and immediately headed to Penn Dixie for the 2023 Dig with the Experts event, which was a huge success and had perfect weather for a very fun two days of collecting the NY Devonian. Found numerous nice prone trilobites, a good selection of the available brachiopods, and the absolute find of the weekend was a sizeable, possibly complete, head shield from a placoderm, which is a dream find for me as they're easily my favorite animals. It was beyond my skill to prep though so I will have to wait until next year to see it uncovered, which will be a great intro the event in 2024 . First, while I didn't do any collecting in Greece or Turkey, I couldn't help but find a few to take pictures of. The breakwater in Istanbul appears to be full of burrow fossils and one coiled cephalopod (maybe) that I'm unsure about the age on. Any ideas? It's likely rock either taken from the Bosporus or from nearby since the blocks are so huge. The next picture is from the walls surrounding the Parthenon in Athens, which I think I read is Cenozoic marine limestone. Next we have the pictures from Penn Dixie - the Placoderm (along with a nice bonus prone trilobite) is split in two and covered in glue so it looks pretty rough now, hopefully it emerges looking good on the other side of the prep process. Not having had enough, the following weekend we returned to NY to try out the famous Deep Spring Road locality which was amazing! My mollusk collection was greatly expanded and I came away with a small rolled Dipleura and the head of a Trimerus, along with a number of Geenops fragments and assorted other material. We also checked out the nearby Museum of the Earth in Ithaca which I highly recommend if you're ever in the area. Next is the Aurora Fossils Festival, which very much did not enjoy the same weather luck as Penn Dixie but was fun all the same. I came away with tons of teeth, my first semi-complete Meg, and two very nice sting ray spines. A nice quality cetacean vertebrae continues to elude me, but they're tough to find there anyway as everything gets so beat up it seems. I was excited to find a fair few complete mollusk shells as well of many different types. They're small but really pretty, they make a nice display! Lastly, a shoutout to the incredible mural at the Fossil Museum, another thing to definitely see if you're ever in the area.
  19. Manticocerasman

    Late devonian placoderm prep:

    Natalie and I have been hunting the late devonian deposits for a while now. And from time to time we do find some small fragmentory placoderm remains. But this time Natalie found something realy exquisite. A well preserved placoderm plate in the shales, after tring to get it out we found out ( the hard way by hitting an other bone fragmet during extraction) that there was a lot more in there than just that one armorplate. So to be sure we had to somehow take back a stone slab from around 60cm long to avoid losing some parts. It has been lying around at home for a while now in wait of some new prepping equipment ( micro sandblaster) and when we recently got the new tools I started the prep of the placoderm. It took a while to clear up as much as possible, with still a few fragments in the harder matrix that I didn't get completely free, but for now the piece is done. Some of the parts that were uncoverd were: The median dorsal plate, pre-and postorbital, antherior supragnatal, Inferognatal and more... the fish should be a type of Coccosteid placoderm. I've already contacted some paleontologists that I worked with before on devonian fish to see if we can get more info out of it. So here is Natalie's placoderm: as found: during the prep: and the end result:
  20. Mahnmut

    Somewhat fishy

    Ahoi, I just finished a model of Dunkleosteus the lazy way, because I don´t have that much time these days. Lazy way means: Skull is a bought model from kaiyodo dinotales, postcranial is a skeletal drawing by Scott Hartmann I modified slightly and printed on some transparent foil. Like the outcome. It is quite small though, only 15 cm, representing a meager 3m in my chosen scale. can anyone tell what the other two are? both recent species, one handmade after a photograph, the other 3d printed from ct data. As I don´t know if I can add tags after posting , I just added the ones I may put in this thread if I ever find the time to build them. After all my Whales, other marine Mammals , Birds and Reptiles I thought it would be nice if I could include some more Reptiles and "Amphibians" (?) If it crossed the border between land and sea, its likeness shall be built by me -some day. -Placodus -Cyamodus -Mastodonsaurus -Tiktaalik -Ichthyostega -Diplocaulus Aloha, J
  21. Back during an April trip to the Widder Formation (Mid-Devonian), I came upon a rather sizeable placoderm. It is very likely the arthrodire, Protitanichthys sp., although it is a bit of wastebasket taxon, but new research is underway. It was pretty much stuck in this rock, and it was only going to come out the hard way. I collected every little bit I could find from that dirty, messy bench, including the impression. Here is the in situ photo:
  22. Hello everyone! I wanted to share a holy grail fossil that I have obtained: a partial skull of Dunkleosteus terrelli found in Cleveland Shale, Ohio This specimen has been confirmed by Zerina Johnson, a leading paleontologist at the Natural History Museum of UK as well as James Boyle who is a leading expert in the field and published academic research papers on Dunkleosteus and other placoderms of the Devonian period. Below is an excerpt from James Boyle on the Dunkleosteus partial skull specimen: "Yes, it's most like a Dunkleosteus based on what I can see. You have both anterior dorsal lateral plates of the thoracic armor there. These are the bones that connected with a mobile joint the head and shoulder regions of the armor. The bone to the bottom left is the internal view of the left anterior dorsal lateral plate. The bone under it is the right anterior dorsal lateral plate in external view. The piece that's skewed to the right a bit in the image is part of the left anterior dorsal lateral plate as well. The easiest way to identify which of the two plates is the external (from the outside) view is that there's a sensory line canal on the one plate (it's straight nearly straight line tracing across the one bone at the top). These are the lateral line system you can still see in some modern fishes and act as pressure sensors to detect movement in the water around the organism. They are only found on the outside of the body." "That oblong bone at the top is probably a piece of the paranuchal plate, but if that's the case it's only a very small fraction of it." Johanson Z (null) Vertebrate cranial evolution: Contributions and conflict from the fossil record. Evolution & Development, doi: 10.1111/ede.12422 Lebedev OA, Johanson Z, Kuznetsov AN, Tsessarsky A, Trinajstic K, Isakhodzayev FB (null) Feeding in the Devonian antiarch placoderm fishes: a study based upon morphofunctional analysis of jaws. Journal of Paleontology, 1 - 18. doi: 10.1017/jpa.2022.54 Charest F, Johanson Z, Cloutier R (2022) The preorbital depression and recess of antiarch placoderms (jawed stem-gnathostomes) revisited from an ontogenetic (saltatory) point of view. Journal of Vertebrate Paleontology, 42 (1) : doi: 10.1080/02724634.2022.2116335 Johanson Z (2021) Paleontology: There are more placoderms in the sea. Current Biology, 31 (16) : R1012 - R1014. doi: 10.1016/j.cub.2021.06.073 van Mesdag SNK, den Blaauwen J, Dean MN, Johanson Z (2020) Hyperossification in the vertebral column of Devonian placoderm fishes (Arthrodira). Journal of Vertebrate Paleontology, 40(1) : e1766477 - e1766477. doi: 10.1080/02724634.2020.1766477
  23. Pliosaur

    Dunkleosteus terrelli partial skull

    Dunkleosteus terrelli - Skull elements Fish Devonian Cleveland Shale - Cleveland, Ohio, USA Very Large 790mm (31 inch) slab with partial skull This is from James Boyle Ph.D a clinical assistant professor specializing in the study of placoderms. He noted: “Yes, it's most like a Dunkleosteus based on what I can see. You have both anterior dorsal lateral plates of the thoracic armor there. These are the bones that connected with a mobile joint the head and shoulder regions of the armor. The bone to the bottom left is the internal view of the left anterior dorsal lateral plate. The bone under it is the right anterior dorsal lateral plate in external view. The piece that's skewed to the right a bit in the image is part of the left anterior dorsal lateral plate as well. The easiest way to identify which of the two plates is the external (from the outside) view is that there's a sensory line canal on the one plate (it's straight nearly straight line tracing across the one bone at the top). These are the lateral line system you can still see in some modern fishes and act as pressure sensors to detect movement in the water around the organism. They are only found on the outside of the body. That oblong bone at the top is probably a piece of the paranuchal plate, but if that's the case it's only a very small fraction of it. I've attached a file with your image rotated a bit and some other images to compare against for Dunkleosteus.” I have contacted and heard back from Dr. Zerina Johnson of the natural history museum, UK who specializes in and published research papers on Devonian placoderms that the partial skull is indeed from Dunkleosteus terrelli Johanson Z (null) Vertebrate cranial evolution: Contributions and conflict from the fossil record. Evolution & Development, doi: 10.1111/ede.12422 Lebedev OA, Johanson Z, Kuznetsov AN, Tsessarsky A, Trinajstic K, Isakhodzayev FB (null) Feeding in the Devonian antiarch placoderm fishes: a study based upon morphofunctional analysis of jaws. Journal of Paleontology, 1 - 18. doi: 10.1017/jpa.2022.54 Charest F, Johanson Z, Cloutier R (2022) The preorbital depression and recess of antiarch placoderms (jawed stem-gnathostomes) revisited from an ontogenetic (saltatory) point of view. Journal of Vertebrate Paleontology, 42 (1) : doi: 10.1080/02724634.2022.2116335 Johanson Z (2021) Paleontology: There are more placoderms in the sea. Current Biology, 31 (16) : R1012 - R1014. doi: 10.1016/j.cub.2021.06.073 van Mesdag SNK, den Blaauwen J, Dean MN, Johanson Z (2020) Hyperossification in the vertebral column of Devonian placoderm fishes (Arthrodira). Journal of Vertebrate Paleontology, 40(1) : e1766477 - e1766477. doi: 10.1080/02724634.2020.1766477
  24. Recently acquired this rare 185mm nuchal bone from Dunkleosteus Terrelli, just thought to share it since there are very few Dunkleosteus material on the commercial market! Attached pictures below just to see the size of this since on most fish it's the size of your thumbnail! Devonian Cleveland Shale Cleveland, Ohio USA 185mm (7.2 inches) nuchal bone
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