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Hi everyone. I received this ichthyosaur tooth from holzmaden, probably ohmden quarry, but I can't identify the genus. in the holzmaden area there are many species of Ichthyosaur. Maybe the most common is Stenopterygius. Can anyone help me identify this tooth please? Size approximately 1,5 cm
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- ichthyosaur
- ichthyosaurus
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From the album: My Echinoid Collection
Diademopsis crinifera Shale Plates Tafelfleins Bed, Posidonia Shale Early Toarcian Age, Early Jurassic (~183 Ma) Holzmaden, Baden-Württemberg, Germany Acquired online, September 2023 A neat couple of black shale plates containing several fragmented specimens of this Early Jurassic echinoid. There are at least 8 notable specimens between the plates, some having associated spines, as well as some smaller test fragments and some loose spines. These urchins are quite small, with the largest ones only being around 1cm (.3937 inches) in diameter.-
- germany
- echinoidea
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Scientists Uncover New Information Regarding Toarcian (Early Jurassic) Mass extinction
Oxytropidoceras posted a topic in Fossil News
Scientists Uncover New Information Regarding an Ancient Mass Extinction Event Florida state University, SciTechDailey, December 22, 2022 The open access paper is: Them, T.R., Owens, J.D., Marroquín, S.M., Caruthers, A.H., Alexandre, J.T. and Gill, B.C., 2022. Reduced Marine Molybdenum Inventory Related to Enhanced Organic Carbon Burial and an Expansion of Reducing Environments in the Toarcian (Early Jurassic) Oceans. AGU Advances, 3(6), p.e2022AV000671. open access Yours, Paul H.-
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- mass extinction
- jurassic
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L.S., I recently purchased an old collection of plant fossils. The boxes also contained an odd couple of non-plants, which I would like to offer up for trade. Ideally, I would like to get some plant fossils in return. Photos below, with scale in centimetres at bottom. Disclaimer: The information below is "as received". I cannot guarantee provenance/identifications are 100% correct since these pieces come from an old collection, plus marine beasties are not really my cup of tea... Kind regards, Tim Specimen A: Large plate with several ammonites (Harpoceras sp.?) on a large plate from the Toarcian (Liassic, Jurassic) of Dudelange in Luxembourg Specimen B: Polished section with several belemnites (Dactyloteuthis sp.?) from the Jurassic of the area around Bayreuth in Bavaria, Germany (note: could use a re-polish to bring out the texture better).
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- luxembourg
- germany
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Hi ! So I went on a walk in some marls in Lozère, France. Usually, I find some amonites and belemnites but this time I decided to change from my usual spot and searched around. I found an isolated marl which is a couple of kilometers away from the main marls which are known to be from the Toarcian. In the whole region (région des grands causses), marls can be either from Toarcian or Pliensbachian according to french wikipedia (https://fr.wikipedia.org/wiki/Marne_(géologie) ). Anyway in this new marl, I didn't find the same fossils as usual, at all. I found mainly gastropods, very small bivalves as well as some rare cases of amonites (which are abundant on the contrary on the other spot). So I was wondering what they were. I believe there are at least two different species in my findings : those on the upper lines look like some pictures of Amphitrochus pictures I found on this forum and on the net. On the second line are what I believe is a second species I didn't really manage to find similar thing on this forum. Under it I put the best looking very small bivalve I found in the very same marl. Do you know what could those be ? I hope it interests you ! Alice
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- pliensbachian
- marl
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Help needed to identify this. Seems to be a dermal denticle. Piensbachian/Toarcian border. 4mm wide field of view.
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- toarcian
- microvertebrate fossils
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Leptolepis coryphaenoides Lower Toarcian Aveyron France
nala posted a gallery image in Member Collections
From the album: fish
Leptolepis coryphaenoides Lower Toarcian Aveyron France -
Hi friends, I went to Marrat formation area (toarcian) to the west of Riyadh and found many? ammonits, they are of varies sizes, it is internal mold, what sp. Is it?
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- saudi arabia
- riyadh
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Hi friends, I went to Marrat formation area (toarcian) to the west of Riyadh and found many? Bivalves, they are of varies sizes, it is internal mold, what sp. Is it?
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- saudi arabia
- toarcian
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Hello, I have recently bought this fossil as an Acrocoelites oxyconus, from the toarcien of Tournadous, France. But after seeing the photos of Ludwigia, and others in the internet, it seems that it is not Acrocoelites oxyconus. The fossil looks to be broken and glued: Thanks!
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From the album: Sketches
4 specimens attached to matrix. Early Jurassic Late Toarcian, thouarsense zone. Found 13 years ago at a construction site in Èvrecy, Normandy, France.-
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- grammoceras
- évrecy
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Hi everyone, I got offered this pair of marine reptile teeth as those of ichthyosaurs, but am having a hard time making my mind up about their identification. I'd therefore like to ask for your opinions. The teeth were found during works around Nancy back in 2004, and, based on other ichthyosaur finds from the region, likely dates the Toarcian stage of the Early Jurassic (though, from what I can tell, Oxfordian marine deposits are also accessible in the area). This makes them roughly the same age as material from the Posidonia Shale/Holzmaden and Whitby, but slightly younger than that of the Lyme Bay area. The above photograph is the only one I have, with the seller being on fieldwork and unable to provide much further information for the next couple of weeks. Although we can safely eliminate marine crocodile as contenders for the original owners of these teeth, and I think they are too big to have belonged to fish, I'm undecided on whether these are just highly worn ichthyosaur teeth or plesiosaur teeth. There's something to be said for both. The tall, slender shape of the teeth and their slight curvature, for instance, would seem to fit plesiosaurian teeth, as would, most significantly, the round root of the bigger tooth. In that case, however, the smaller tooth does seem a bit stubby, and the traces of ornamentation along the midsection of the larger tooth surprisingly equidistantly spaced. Generally, the morphology of the smaller tooth to me suggests ichthyosaur rather than plesiosaur. But if that were the case, I'd expect either enamel folds on the crowns themselves, folds on the root, or both (even when ichthyosaur teeth have smooth enamel, I find they still have folds on their roots). I'd also expect the root to be more polygonal in shape, somewhere in the range of triangular to (rounded) square. This is not the case. Now there seems to be some ornamentation midway up the larger specimen which equidistant spacing correlates well with patterns of the folds found on ichthyosaur teeth, thus may indicate the tooth is ophthalmosaurid and therefore Oxfordian rather than Torcian in age. The below image I drew up makes the comparison: As you can see, the match is less then ideal, as the top part of the French tooth is completely devoid of enamel folds, whereas in an ophthalmosaurid tooth the plicidentine folds actually taper out until the enamel is clear. @belemniten, however, posted images of a couple of his ichthyosaur teeth from Holzmaden, one of which appears to show a similar pattern as visible in the middle of the French tooth under consideration here, including what appears to be a round root: However, when looking at other images of the same tooth, it turns out that the root does have folds, as you'd expect from ichthyosaur teeth: Similarly, the below tooth seems to have a superficially similar appearance to the French tooth for the hairline cracking of the enamel, and the fact that enamel appears to be missing from the crown immediately above the root proper (which, again, exhibits folds, however). Still, if the "smooth round root" on the French tooth would've been covered by enamel as well, this would make for a very tall tooth as far as ichthyosaurs go. As illustrated by the specimen below (source), though, ichthyosaur teeth do occasionally have round roots: Moreover, the folds on the root don't always run the full height of it (image source): Lastly, as the specimen below demonstrates (source), the entire root can look completely smooth, presumably from wear: As such, I'm wondering whether the French tooth specimen might not be a very worn ichthyosaur tooth, with its parts being composed as such: This doesn't particularly make too much sense to me either, as the part of the root with folds is rather long and has a very abrupt transition into the remainder of the root. In addition, it raises the question of how the tooth would've gotten so worn. Though I understand there are fluvially exposed sites around Nancy, could this have caused the wear we're seeing. Or would the wear rather be peridepositional? So, I guess I can summarize my questions as: Do these look like plesiosaur or ichthyosaur teeth? If plesiosaurian, what would the equidistant striations on the midsection of the tooth be? If ichthyosaurian, do these teeth look more ophthalmosaurid or pre-ophthalmosaur? How might the wear I think I'm seeing be explained? Thanks for the help! cc @paulgdls @PointyKnight @DE&i @Welsh Wizard @RuMert @FF7_Yuffie
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From the album: Cephalopods Worldwide
ø 77mm. Pyritized. Early Jurassic. Middle Toarcian. bifrons zone. fibulatum horizon. Found in the Causse du Larzac, Aveyron, France.- 1 comment
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- porpoceras
- france
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From the album: Nautiloidea
11cm. From the upper Toarcian in the Lafarge Cement quarry at Belmont near Lyon, France. -
Hi friends and happy holidays, I went to Marrat formation area (toarcian) to the west of Riyadh and found many ammonites, one of them is Nejdia bramkampi , it is one of the most beautiful ammonites you can find , enjoy.
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- saudi arabia
- nejdia bramkampi
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Hi friends and happy holidays ,can you help me with this ,I went to Marrat formation area (toarcian) to the west of Riyadh and found many ammonites ,they are small , thin , 6-10 cm wide and 4-5 cm high , it was a surface find . What sp. could they be?
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- saudi arabia
- mrrat formation
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From the album: Cephalopods Worldwide
4cm. Found in a concretion at Ravenscar, Yorkshire, GB. Early Toarcian bifrons zone.- 1 comment
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- pseudolioceras
- toarcian
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I keep finding small rocks at the base of banks alongside the road, around the area where I live in Bath, UK. Most of them contain bivalves but I keep coming across this shape which I can’t recognise (picture 1) Picture 2 is a close-up of rock A which seems least weathered. I think these are the imprints left behind by something but I also have an example of what I think could be the actual object itself (please excuse my lack of terminology!) but it’s tiny compared to the other three examples (picture 3) Any help with this would be great thanks.
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From the album: Cephalopods Worldwide
6.5cm. From the Whitby Mudstone Formation, bifrons Zone, braunianus Subzone of the lower Toarcian at Saltwick Bay, Yorkshire.-
- zugodactylites
- toarcian
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From the album: Cephalopods Worldwide
6cm. Bifrons Zone, Lower Toarcian. From the Lafarge Quarry at Belmont near Lyon, France.-
- porporoceras
- toarcian
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Dwarf Brachiopoda from early Toarcian Koninckella fauna in Portugal (Polymorphum Zone, Semicelatum subzone), comprising particularly Koninckella liasina, Nannirhynchia pygmaea and Pseudokingena deslongchamps. Koninckinidae became extinct in the early Toarcian and has minute size and peculiar shape (that is very similar to that of the Paleozoic strophomenids). Comas-Rengifo, M.J., Duarte, L.V., García Joral, F., Goy, A., 2013. Los braquiópodos del Toarciense Inferior (Jurásico) en el área de Rabaçal-Condeixa (Portugal): distribución estratigráfica y paleobiogeografía. Compt. Rendus Geosci. 100 (1), 37–42. Comas-Rengifo,M.J., Duarte, L.V., Félix, F.F., García Joral, F., Goy, A., Rocha, R.B., 2015. Latest Pliensbachian–Early Toarcian brachiopod assemblages from the Peniche section (Portugal) and their correlation. Episodes 38, 2–8.
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- koninckella fauna
- semicelatum subzone
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Reference here. Comas-Rengifo, María & Duarte, Luís & García Joral, Fernando & Goy, A. (2013). The brachiopod record in the Lower Toarcian (jurassic) of the Rabaçal-Condeixa region (Portugal): Stratigraphic distribution and palaeobiogeography [Los braquiópodos del Toarciense Inferior (Jurásico) en el área de Rabaçal-Condeixa (Portugal): Distribución estratigráfica y paleobiogeografía]. Comunicacoes Geologicas. 100. 37-42.
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- levisoni zone
- telothyris pyrenaica dubar 1931
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Belongs to the so-called “Koninckella Fauna” from the base of the Dactylioceras semicelatum Subzone.
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Belongs to the so-called “Koninckella Fauna” from the base of the Semicelatum Subzone.
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- cabo carvoeiro fm
- toarcian
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