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A few weeks ago some friends and I visited a site near Braidwood in southern NSW (3 hours south of Sydney) for middle-late Devonian fish. The site was first published in Ritchie (1984) with the description of Placolepis budawangensis, a phyllolepid known only from this locality. This species is one of the two most common here, with the other being Bothriolepis longi (see Johanson 1999). So far, only these two species have been described from this locality but acanthodian spines and sarcopterygian scales are also known. All fish fossils from this locality occur in within a 75cm band of red siltsone and are mostly just disarticulated plates, but the P. budawangensis holotype is still fairly well articulated. The plates of both species are very recognisable, the Placolepis usually have lovely parallel ridges whereas the Bothriolepis are covered in tiny bumps. Some photos of the siltsone band with some fish plates exposed on top. Peter did a great job on this hole, it's not easy work! The specimens from this locality are quite weathered, so the bone is usually quite poor and doesn't split well. They still look nice, but I chose to dissolve away the bone in hydrochloric acid to latex the cavity for photography. Here are some as found: Placolepis: Bothriolepis: Some bone in cross section (the horizontal black dotted lines): Here are some latex casts of specimens after acid preparation. The latex is blackened with ink, then whitened with ammonium chloride for high contrast photos. Much easier to make out features in these than the unprepared specimens! Bothriolepis longi plates and pectoral fins (compare with figures in Johanson 1999): Placolepis budawangensis: Sarcopterygian scale(?): No idea on this one! After the fish site, we quickly stopped in at a road cutting which yields occasional Devonian plant fossils. Nothing too exciting, but still nice to find some Devonian plants! That's all for now, I might post more ammonium chloride photos when I take the next batch. Hope you enjoyed!

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!

Hi all, This is a follow-on from the first post in my ‘Adventures in Thin Sectioning’ thread where I showed this fossil from the Aust bone bed. I wanted to have it scanned so that I have a record of both halves before I try to make histological sections of the ‘offcut’. Luckily, my department has a micro X-ray CT scanner (Nikon XT H 225ST) and when there was a gap in demand I was able to book time for a couple hours of scanning. I got three separate scans done, the two pieces of the Aust block done together and then two articulating fragments from the Woodhill Bay Fish Bed at Portishead which are full of upper Devonian placoderm and sarcopterygian fragments. Florists foam is used to hold the pieces in place during scanning as it is easy to press the rocks into and low enough density as to not interfere with the scan. The scan for the Aust block took a little over an hour, and after reconstruction the vertebra is differentiable. The scan isn’t brilliant due to the abundance of pyrite in the stone which scatters the X-rays but it should hopefully be good enough to segment out the bone by hand and make a 3D model, so mission accomplished! The scans for the Portishead material were much shorter exploratory scans (>30 minutes) but turned out better due to the lower density sandstone matrix and lack of pyrite. Both pieces are full of fragments of scale and bits of bone but the larger of the two has a couple particularly interesting features. A large ?spine which I haven’t yet identified: A fragment of jaw with three teeth, likely belonging to the Sarcopterygian Holoptychius: Using a free program called Drishti I’ve been able to quickly reconstruct the Portishead scans in 3D and while the differentiation between bone and matrix isn’t fantastic it is good enough to get an idea of the spatial arrangement of the fragments. I intend to spend some time learning to segment out the fragments individually in Dragonfly (another free program for working with slice data) but am currently struggling with a few bugs so that will have to come later. The two fragments as rendered volumes in rough alignment: A rough rendering of the locations of the bone/scale fragments in both blocks. I believe the majority of the scales are Holoptychius as it is the most abundant taxa in this deposit: Close up on the area with the fragment of jaw, the three teeth are clearly visible as well as the stumps of two others: Thanks for looking, let me know if you have any questions.

The Sarcopterygian fish (also called lobed-fined fish) are an ancient group of fish that emerged in the Late Silurian 425 Million Years ago and gave rise to the direct ancestors of the first land vertebrates, the amphibians during the Late Devonian. Today represented by the still living Coelacanths and Lungfish, These fish were incredibly common and diverse during the late Paleozoic. But the Permian-Triassic Extinction Event 252 Million Years ago nearly decimated the group. But thankfully some of the Sacopterygii survived and all living Sarcopterygians and trace their origins to these few hardy survivors. Here's a list of all currently known Sacropterygian fish genera and families that survived the Permian-Triassic Extinction Event. If I forget any examples, please let me know and I'll add the examples to the list promptly. Sarcopterygii Dipnoi (Lungfish) Gnathorhiza (Dipnoid) (Carboniferous-Early Triassic, 318.1-247.2 Million Years ago) http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=90709 https://www.researchgate.net/publication/278743788_Environmental_significance_of_lungfish_burrows_Gnathorhiza_within_Lower_Permian_Wolfcampian_paleosols_of_the_US_midcontinent https://www.researchgate.net/publication/291808594_The_westernmost_occurrence_of_Gnathorhiza_in_the_Triassic_with_a_discussion_of_the_stratigraphic_and_palaeogeographic_distribution_of_the_genus Ceratodontiformes https://www.researchgate.net/publication/284186167_The_first_find_of_Permian_ceratodontids_Dipnoi_Osteichthyes_in_Russia Coelacanthiformes (Coelacanth fish) Coelacanthus (Coelacanthid) (Carboniferous-Early Triassic, 314.6-247.2 Million Years ago) http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=34911 https://www.researchgate.net/publication/226724498_Erratum_to_A_coelacanthid-rich_site_at_Hasbergen_NW_Germany_taphonomy_and_palaeoenvironment_of_a_first_systematic_excavation_in_the_Kupferschiefer_Upper_Permian_Lopingian https://www.researchgate.net/publication/265184906_Coelacanths_from_the_Middle_Triassic_Luoping_Biota_Yunnan_South_China_with_the_earliest_evidence_of_ovoviviparity I hope you all find this list helpful!!!

So an interesting summer. As some of you might know, Parks and Recreation came down hard on the Red Hill site while I was working there. At some point, the site had been transferred to Forestry, ya go figure. So there has not been an active permit for some time. But I was homeless and in need of a project so I was able to connect with Prof. Dave Broussard of Lycoming College and shift my focus to the sites along Rt 15 north of Williamsport. Still Catskill although the exposures at Powys Curve are Sherman Creek (Frasian) member instead of the Duncannon (Fammenian). I had collected there with my son Ian a while ago but was at one of the less productive sites I've been visiting this summer. This is the find of the summer (maybe lifetime). It is a Tristichopterid, like Hyneria. Its at the Academy of Natural Sciences in Philly and just being described now for a publication by Ted Daeschler.

Red Hill is a site I first went to 10 years ago with my son, Ian who was 10 at the time. It is a very deep road cut into the uppermost part of the Catskill Formation representing a late Fammenian river system that was draining the Acadian mountains to the east and emptying into the inland sea in western PA and OH. It is one of a handful of sites in the world where Devonian tetrapods have been found. The site has fossil layers in both channel margin (red layers) and flood plain (gray-green layers) facies. While it is an active research site and groups go there under the understanding that anything of scientific importance will be donated to the museum, there is a lot there that is redundant in the collections and we've been able to retain. In 2014, Ian found an exceptionally preserved moderately large osteolepiform, Hyneria (Tristichopteridae). Some of the material went into the re-description of Hyneria, much we have been allowed to take home. Since then the project has expanded to a search for more tetrapod material using the jackhammer and generator the museum purchased. This may require multiple posts. I'll start with the jaws recovered over 2014/15 seasons. This lens containing most of the head from apparently a single individual. Here Ian is working with Ted Daeschler and Doug Rowe (site manager) of the Academy Of Natural Sciences in Philadelphia. Here are some images of the jaw material after removal and after prep by Fred Mullison of the ANSP. Lower left jaw after removal. This is the lower right jaw (right) and the vomer and very impressive fang. Amazingly, in 2016, we went back. I was leading a trip for DVPS. Ian found this amazing but poorly prepped jaw (I did this one). Here are a pair of cleithrums, about 29 cm long. The attachments for the scapulocoracoid are clearly visible between 17 and 21 cm. Here is part of the parietal shield. More to follow.