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Loc: https://www.geopark-thueringen.de/entdecken-erleben/nationale-geotope/standard-titel Age: Triassic, Keuper For wchich Archosaur, this tooth belongs? I know that it's hard to say, but maybe somebody can do this

Hi everyone, I recently acquired the below fossil, taking a chance as to what it might be. It came labelled as Mixosaurus sp. from the Keuper (Upper Triassic) of Kirchberg an der Jagst, but I can't place the bone... Initially, I thought it could be a broken mixosaur coracoid, though the shape doesn't match at all. In the below image the break is circled in blue, with the red circle marking a projection from the bone that I would not expect to be present if the bone were indeed a (mixosaur) coracoid, as shown in the drawing next to it (from Jiang, Schmitz, Hao and Sun, 2006. A new mixosaurid ichthyosaur from the Middle Triassic of China). Moreover, according to the Handbook of Paleoherpetology on ichthyopterygians, mixosaurs were no longer around in the Upper Triassic. Nor is it the coracoid of a more derived species of ichthyosaur, as these have neither notch nor the aforementioned projection - as is illustrated by the image below (don't mind the incorrect bone ID on the label). Thus, in line with a suspicion I already had, it doesn't look like this is a mixosaur coracoid at all. But what could it be then? Well, one option seems to be that this could be a pelvic bone, either of a shastasaurid or other early ichthysaur like Cymbospondylus sp. or Besanosaurus sp., to judge by the notch at the top of the bone. The below drawings, taken again from the Handbook of Paleoherpetology, demonstrate what I mean, as does the supplied image of a shastasaurid pelvic girdle from China (figure 4 from Shang & Chun, 2009. On the occurrence of the ichthyosaur Shastasaurus in the Guanling biota (Late Triassic), Guizhou, China): Unfortunately, however, most of the species in which this condition occurs don't seem to have survived beyond the Middle Triassic. What's more, reference material I have of a cast of Besanosaurus sp. taken in the Museo Civico dei Fossili die Besano don't make things much clearer for that particular species, as such a notch cannot be observed (nor am I entirely sure it's visible in the above photograph of the Shastasaurus tangae): Similarly, the best preserved Cymbospondylus sp. specimen at the Zoological and Palaeontological Collections of the University of Zürich is of little contribution, because of it lacking the hind part of its body. A second specimen, however, does seem to preserve the pubis (albeit in less direct association): This being the case, could it my bone be an early ichthyosaurian pubis? Or should we still rule that out for the above reasons (i.e., the species showing the characteristics notch not being recorded for the Upper Triassic)? What about other options? As can be seen in the below image, the shape of the bone looks kind of reminiscent of a plesiosaur (here , at the Zoological and Palaeontological Collections of the University of Zürich) pubis, though obviously a lot smaller. Could it be, then, that rather than stemming from an ichthyopterygian the bone derives from a sauropterygian? If so, placodont is not very likely, since, as far as I know, 1) these were not around during the Upper Triassic, and 2) the shape of the bone does not seem to match elements from either pectoral or pelvic girdles amongst the little reference material I have of Placodus gigas. Something of a pachypleurosaur then? Doesn't look likely either, based on some reference material I took of a Serpianosaurus mirigiolensis specimen at the Museo dei fossili del Monte San Giorgio in Meride: Looking at nothosaurid specimens from the Paläontologische Sammlung of the MUT in Tübingen (first) and Zoological and Palaeontological Collections of the University of Zürich (rest: Ceresiosaurus sp.), although not providing a direct match, seem more promising as comparison material:

Hi, Carrying out a spring clean and I found this from an old school geology field trip I took in about 1984. This would have been from the Birmingham Ridge (UK) of Keuper bed Sandstone which dates to the Triassic. Unfortunately I cant be more precise on the location as my memory has faded and I have lost my old notes but it would have been somewhere in the proximity of Barr Beacon. According to the literature this would have been a river delta - to my eye these look more like ripples you'd find on a shallow beach. Or maybe they are nothing - I thought I'd share to see what the experts think. What I love about these - if they truly are fossilised ripples - is their fragility. A true snapshot in time frozen forever. Thanks for looking, Carl