snolly50 Posted November 3, 2021 Share Posted November 3, 2021 Here is another Mosasaur piece. Please comment, as to its qualities. What jaw positions are represented? Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See Link to comment Share on other sites More sharing options...
snolly50 Posted November 12, 2021 Author Share Posted November 12, 2021 @pachy-pleuro-whatnot-odon @LordTrilobite I am considering acquisition of the piece above for a prep project in the Spring. I have evaluated it to the best of my ability via the photos; but would appreciate your opinions. The best I can see of the visible teeth in the upper portion; they exhibit some fracturing, but the juncture of the crowns/roots appears natural. I also lean toward "as found" authenticity because of the appearance of the matrix obscured and damaged portion on the lower half. The fossil is from Morocco, of course. It is very large - two feet in length and weighing 85 pounds. Do you have an opinion as to the life positions represented by the topmost and lower visible sections? Please comment, if you have time. I appreciate your observations. Thank you for any assistance. Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted November 12, 2021 Share Posted November 12, 2021 At first glance I agree with your assessment that this does indeed look like quite an authentic piece. While I would personally not go for a piece like this due to all the breakages and therefore lack of detail and display value, as well as it being easy to hide embellishments under the cover of natural damage, I don't see any obvious red flags on this piece. That is, there are some suspicious lines running at the point of connection between root and crown on the first two teeth from the left, but I think those are naturally present. The teeth also seem to match up quite nicely, if many of them show signs of damage. The species would be Prognathodon cf. giganteus/sp. (whichever you prefer, a discussion is still ongoing) with them being marginal teeth. Hard to say whether maxillary or dentary, though, but I suspect the latter as the teeth look a bit stubbier than I believe those on the maxillary would be. I'll take the liberty of including @Praefectus, by the way, to see what he thinks about the piece... 1 1 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
Praefectus Posted November 12, 2021 Share Posted November 12, 2021 I echo what Alexander said. I'm not seeing any explicit sections of repair or restoration, but I would recommend passing on the jaw anyways because there are better specimens available. I also agree with the Prognathodon identification. 34 minutes ago, pachy-pleuro-whatnot-odon said: The species would be Prognathodon cf. giganteus/sp. I might be reading too much into it, but in a recent talk given by Dr. Nick Longrich, he really briefly showed a picture of a Moroccan Prognathodon skull and called it "Prognathodon or something like it." The way he said it made me wonder if he might be alluding to creating a new genus. 1 Link to comment Share on other sites More sharing options...
snolly50 Posted November 12, 2021 Author Share Posted November 12, 2021 @pachy-pleuro-whatnot-odon Many thanks for your assessment. Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See Link to comment Share on other sites More sharing options...
snolly50 Posted November 12, 2021 Author Share Posted November 12, 2021 @Praefectus Thanks, much appreciated. Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See Link to comment Share on other sites More sharing options...
pachy-pleuro-whatnot-odon Posted November 12, 2021 Share Posted November 12, 2021 9 minutes ago, Praefectus said: I might be reading too much into it, but in a recent talk given by Dr. Nick Longrich, he really briefly showed a picture of a Moroccan Prognathodon skull and called it "Prognathodon or something like it." The way he said it made me wonder if he might be alluding to creating a new genus. That'd be interesting, because the genus Prognathodon is not restricted to Morocco, and I believe the Moroccan species show a lot of synapomorphies with those from other parts of the world. It could be that his phrasing was just meant to indicate that right now it's just a broad label, without any specific species identity. Although I recently read somewhere - but still need to verify this - that Prognathodon anceps is no longer a valid name? If so, the only other definition currently available for Moroccan prognathodontids would be P. giganteus (hence my referencing it here as such again). We'll have to see how this develops... 1 'There's nothing like millions of years of really frustrating trial and error to give a species moral fibre and, in some cases, backbone' -- Terry Pratchett Link to comment Share on other sites More sharing options...
Praefectus Posted November 12, 2021 Share Posted November 12, 2021 "Prognathodon anceps" never really was a valid name. It is the result of Arambourg 1952's Mosasaurus cf. anceps being re-named Liodon anceps (or the Cope spelling Leiodon anceps), and the genus Liodon/Leiodon being synonymized with Prognathodon in Schulp et al., 2008 (same paper that named Prognathodon kianda). If you follow all the steps, you end up with "Prognathodon anceps", but there is a major issue. The Moroccan "P. anceps" looks nothing like the (now lost) holotype of Leiodon anceps. The taxonomy is a complete mess. Adding to the confusion is the fact that fossil dealers have slapped any combination of the above names together when selling Moroccan Prognathodon fossils. Prior to 2021, Bardet separated P. giganteus and the Moroccan Prognathodon by referring to the latter as P. sp. nov. Strangely, her recent publications dropped both P. giganteus and P. sp. nov. in favor of P. saturator. I have no clue what the researchers are thinking. Personally, I use the dubious name "Prognathodon anceps" informally. This is only because there are many more than one Prognathodon tooth morphs in the Moroccan phosphates and referring to all the unknown morphs as P. sp. nov. is likely to get confusing really fast. 1 Link to comment Share on other sites More sharing options...
Praefectus Posted November 12, 2021 Share Posted November 12, 2021 14 minutes ago, pachy-pleuro-whatnot-odon said: the genus Prognathodon is not restricted to Morocco I think the whole genus needs to be overhauled. The former Leiodon species need to be split out of Prognathodon again. P. currii and P. kianda need to be re-assessed to determine whether they really are Prognathodon or not. P. giganteus needs to be re-evaluated to determine if the holotype is diagnostic. The Moroccan P. sp. nov. needs a thorough description... Seems simple enough, right? It's only like 4-5 PhDs worth of research. 1 Link to comment Share on other sites More sharing options...
LordTrilobite Posted November 12, 2021 Share Posted November 12, 2021 No red flags here. It all looks authentic. It's a bit broken up so that does make it harder to identify which jaw part it is. But I think it fits best with lower jaw. And it does indeed look like Prognathodon. Olof Moleman AKA Lord Trilobite Link to comment Share on other sites More sharing options...
snolly50 Posted November 13, 2021 Author Share Posted November 13, 2021 @Praefectus @pachy-pleuro-whatnot-odon @LordTrilobite Thank you for your opinion on this piece. Having the thoughts of the experienced members who responded is valuable to me. Evaluating from photos is, of course, not ideal; but having a positive nod from several well informed folks, bolsters confidence in my established view. I did purchase the fossil. It does have condition issues that might be avoided in a better preserved specimen - but, the price was too attractive to pass up. It will be my Spring prep project. Once in hand, I will determine the optimal course to achieve the best possible display outcome. The matrix block is six inches thick. I am intrigued to evaluate the surface not visible in the photos. I will probably be removing a great deal of matrix at the upper portion behind the prominent teeth (leaving those teeth free-standing) and am curious if additional material will be revealed. Thanks again for your help. 2 Human beings, who are almost unique in having the ability to learn from the experience of others, also are remarkable for their apparent disinclination to do so. - Douglas Adams, Last Chance to See Link to comment Share on other sites More sharing options...
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