Ichthyotitan, new giant ichthyosaur from Late Triassic of UK + large ichthyosaur vertebra from Kama River, Russia (free pdfs)

[Ben Creisler]

Ben Creisler

bcre...@gmail.com

New ichthyosaur papers:

Free pdf:  

 
Ichthyotitan severnensis gen. et sp. nov.

Dean R. Lomax, Paul de la Salle, Marcello Perillo, Justin Reynolds, Ruby Reynolds & James F. Waldron (2024)
The last giants: New evidence for giant Late Triassic (Rhaetian) ichthyosaurs from the UK
PLoS ONE 19(4): e0300289
doi: https://doi.org/10.1371/journal.pone.0300289
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0300289


Giant ichthyosaurs with body length estimates exceeding 20 m were present in the latest Triassic of the UK. Here we report on the discovery of a second surangular from the lower jaw of a giant ichthyosaur from Somerset, UK. The new find is comparable in size and morphology to a specimen from Lilstock, Somerset, described in 2018, but it is more complete and better preserved. Both finds are from the uppermost Triassic Westbury Mudstone Formation (Rhaetian), but the new specimen comes from Blue Anchor, approximately 10 km west along the coast from Lilstock. The more complete surangular would have been >2 m long, from an individual with a body length estimated at ~25 m. The identification of two specimens with the same unique morphology and from the same geologic age and geographic location warrants the erection of a new genus and species, Ichthyotitan severnensis gen. et sp. nov. Thin sections of the new specimen revealed the same histological features already observed in similar giant ichthyosaurian specimens. Our data also supports the previous suggestion of an atypical osteogenesis in the lower jaws of giant ichthyosaurs. The geological age and giant size of the specimens suggest shastasaurid affinities, but the material is too incomplete for a definitive referral. Ichthyotitan severnensis gen. et sp. nov., is the first-named giant ichthyosaur from the Rhaetian and probably represents the largest marine reptile formally described.

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A. S. Bakaev, A. V. Sergeev & N. G. Zverkov (2024)
First Find of an Ichthyosaur from Udmurtia (Cis-Ural Region, Russia)
Paleontological Journal 58(2): 226–231
doi: https://doi.org/10.1134/S0031030123600245
https://link.springer.com/article/10.1134/S0031030123600245

Free pdf:
https://www.researchgate.net/publication/379403517_First_Find_of_an_Ichthyosaur_from_Udmurtia_Cis-Ural_Region_Russia


A dorsal vertebra of an ichthyosaur is described from the fluvial deposits of the Kama River (Votkinsk District, Udmurt Republic, Russia). This vertebra belonged to a fairly large ichthyosaur about 5–6 m long, apparently one of the largest ichthyosaurs known from European Russia. The find is redeposited, and it is problematic to establish its exact age: most likely, the vertebra was brought by the Kama River from Jurassic–Cretaceous outcrops located upstream.

[Ben Creisler]

News:

University of Manchester paleontologist Dean Lomax unearths what may be the largest known marine reptile

https://www.manchester.ac.uk/discover/news/manchester-paleontologist-unearths-what-may-be-the-largest-known-marine-reptile/

https://phys.org/news/2024-04-paleontologists-unearth-largest-marine-reptile.html

https://www.discoverwildlife.com/animal-facts/reptiles/gigantic-ichthyosaur-discovered-in-the-uk
https://www.theguardian.com/science/2024/apr/17/ichthyosaur-fossils-somerset-may-be-largest-marine-reptile-that-lived

https://www.livescience.com/animals/extinct-species/giant-82-foot-lizard-fish-discovered-on-uk-beach-could-be-largest-marine-reptile-ever-found

https://www.nytimes.com/2024/04/17/science/ichthyosaur-fossil-largest.html

https://cosmosmagazine.com/history/palaeontology/largest-marine-reptile-triassic/

https://www.discovermagazine.com/the-sciences/species-of-ichthyosaur-is-largest-known-marine-reptile-at-80-feet-long

https://www.washingtonpost.com/science/2024/04/17/largest-marine-reptile-ichthyosaurs/

[Gregory Paul]

Here we go again with these exaggerations of super sized sea reptiles. One of the authors claimed on radio that Ichthyotitan got as big as blue whales. Yeah right. Notice no technical restoration of the animal showing such. As I documented via rigorously produced skeletals and extrapolations in the Princeton Field Guide to Mesozoic Sea Reptiles, no known marine reptiles fossil documents any that exceeded about 20 m and 20 tonnes. The Ichthyotitan suranigulars do not demonstrate otherwise -- one issue is that surangular length relative to other skull and skeletal dimensions is extremely variable in basal ichthyosaurs. It is interesting that the paper does not make an effort to estimate mass. Same with the Sander et al. paper on new basal ichthyosaur remains. I suspect the debunking of super massive sea reptiles in the field guide as a lot to do with that.

GSPaul

On Wednesday, April 17, 2024, 1:51:34 PM EDT, Ben Creisler <bcre...@gmail.com> wrote:

Dean R. Lomax, Paul de la Salle, Marcello Perillo, Justin Reynolds, Ruby Reynolds & James F. Waldron (2024)

The last giants: New evidence for giant Late Triassic (Rhaetian) ichthyosaurs from the UK
PLoS ONE 19(4): e0300289
doi: https://doi.org/10.1371/journal.pone.0300289
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0300289


Giant ichthyosaurs with body length estimates exceeding 20 m were present in the latest Triassic of the UK. Here we report on the discovery of a second surangular from the lower jaw of a giant ichthyosaur from Somerset, UK. The new find is comparable in size and morphology to a specimen from Lilstock, Somerset, described in 2018, but it is more complete and better preserved. Both finds are from the uppermost Triassic Westbury Mudstone Formation (Rhaetian), but the new specimen comes from Blue Anchor, approximately 10 km west along the coast from Lilstock. The more complete surangular would have been >2 m long, from an individual with a body length estimated at ~25 m. The identification of two specimens with the same unique morphology and from the same geologic age and geographic location warrants the erection of a new genus and species, Ichthyotitan severnensis gen. et sp. nov. Thin sections of the new specimen revealed the same histological features already observed in similar giant ichthyosaurian specimens. Our data also supports the previous suggestion of an atypical osteogenesis in the lower jaws of giant ichthyosaurs. The geological age and giant size of the specimens suggest shastasaurid affinities, but the material is too incomplete for a definitive referral. Ichthyotitan severnensis gen. et sp. nov., is the first-named giant ichthyosaur from the Rhaetian and probably represents the largest marine reptile formally described.

P. Martin Sander, René Dederichs, Tanja Schaaf, Eva Maria Griebeler in PalZ (2024)
Cymbospondylus (Ichthyopterygia) from the Early Triassic of Svalbard and the early evolution of large body size in ichthyosaurs
PalZ (advance online publicaiton)
doi: https://doi.org/10.1007/s12542-023-00677-3
https://link.springer.com/article/10.1007/s12542-023-00677-3


Ichthyosaurs were a highly successful group of marine reptiles in the Mesozoic. The ichthyosaur radiation is part of the recovery from the Permian-Triassic mass extinction. In the Early Triassic, this group underwent extensive global radiation, filling ecological niches for the first time that were later occupied by various other lineages of marine amniotes. However, the evolution of body size in ichthyosaurs is not fully understood, as most large-bodied taxa originate from the Middle Triassic and later, and are mostly known from only a few specimens. In this study, we describe three articulated posterior dorsal vertebrae (IGPB R660) of the ichthyosaur Cymbospondylus sp. from the latest Olenekian Keyserlingites subrobustus zone of the Vikinghøgda Formation of the Agardhdalen area, eastern Spitsbergen, Svalbard. We numerically estimated the total body length of IGPB R660 from dorsal vertebral centrum length using a comparative dataset of other species of the genus and two different allometric analyses. This approach yields total length estimates of 7.5 m and 9.5 m for the individual, respectively, the highest for any unambiguous Early Triassic ichthyosaur find. Earlier, higher estimates of 11 m were based on taxonomically and stratigraphically inconclusive material but do not appear unreasonable based on evidence provided in this paper. Our study underscores both the rapid ecosystem recovery after a major mass extinction and extremely rapid increases in body size in ichthyosaurs after their adaptation to a secondarily aquatic lifestyle.

[Leo Sham]

Let me take this opportunity to say hi to the relocated group, and voice my heartfelt (well, a bit of emotion is okay?) agreement with Greg Paul on this.

One may further suggest that this "gigantic marine reptile" [GMR] stuff if not even bad science, but quite probably a mere cultural construct. While the WWW was not common then, this idea was certainly not widespread even in the public/layman literature, not to mention scientific papers, before the turn of the (21st) century, when BBC's WWD made up a gigantic Liopleurodon. Before that, GMR was almost unmentioned of: Shonisaurus was of course large (but no one said it was blue whale sized). I only remembered some vague mentioning of the purported marine[?] crocodile Chthonosuchus to be "a hundred feet long". And then there was Betsy Nicholl's giant ichthyosaur skull, which got DOWNSIZED from the initial hype. Otherwise, it was then trendy to downsize "Megalodon" to a 40-50 footer (though still twice the length i.e. 8 times the weight of a large great white), and I distinctly remember reading a short (6 page) paper questioning the gigantic size of the prehistoric filter feeder exemplar Leedsichthys. Well, after BBC's lead, things/minds changed.

It seems that anything beyond twenty meters must have been/is/will be a filter feeder rather than a megapredator. Between 15-20 meters, a gray zone - sperm whales present and past, Basilosaurus, upper sized "Megalodon", Mosasaurus, (Spinosaurus).
Please feel free to correct me. This idea had been my hunch for some time and I long to learn more.

[Jura]

SVPOW talked a bit about this recently and I'll say what I said there. We should stay cognizant of the fact that very large sea life is going to be exceedingly rare to find in the fossil record. We have no fossils of blue whales or blue-whale-sized whales (Perucetus  may be the exception) in the fossil record in large part because when these animals die, it's often well away from the continental shelf. If you get stuck on the sea floor then you are more likely to get eroded into oblivion long before any aspiring paleontologist is going to find you.

So, were there blue-whale-sized extinct sea animals? Maybe. Will we ever find them? Probably not. As for the need for a large sea animal to be a filter feeder, I remain skeptical there. We have an N of 1 for extant giant sea life (whales). It's easy to assume that what works for whales is what works for all animals, but assumptions like that need to be tested. Baleen whales got huge by feeding off krill. Could ichthyosaurs get equally as large by feeding off ammonites (which were likely as abundant)? That the second largest of our extant marine giants is the sperm whale, and that this species lives off fish and squid, tells me that filter feeding may not be the necessity that it is commonly portrayed to be.

Cheers,

Jason

[Gregory Paul]

The below analysis has problems. Truly gigantic whales only evolved in the last few million years, in association with the very atypical food generating ocean currents produced by the ice age, this is well documented in the technical literature. There are fossils of them on the continental fringes, but those are inaccessible at this time because we are currently in an interglacial that has drowned the general Pleistocene coastlines (the glacial periods are about ten times longer than the interglacials). In say another 20K years when the massive ice sheets have returned after this temporary greenhouse thing is over, then blue, fin, right, sperm whale fossils will be accessible to paleozoologists. 

If there would fin-blue whale sized cetaceans swimming about prior to the late Pliocene-Pleistocene we should have found them by now. There are lots of Oligocene-Pliocene whale bones in collections and they are at most humpback-greywhale dimensions. Perucetus was 50-70 tonnes, it was not supersized as the describing paper way miscalculated without a skeletal restoration to show it could be anywhere close to blue whale size much less even larger (their own skeletal restores a mass under their 85 t minimum). 

There is not a single marine reptile bone that even begins to suggest they got to the dimensions of blue, fin, sperm, right whales over the last quarter billion years. So far everything clearly or very probably is under 20 tonnes. The Ichthyotitan jaw elements might maybe exceed that a little, but don't hold your breath on that. 

GSPaul

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[Gregory Paul]

It is of note that sea reptile size got hyped in the search for ratings in dinocable programming (similar to how megalodon might still be alive! also got pushed on cable for the same reason), and while that got slapped down there seems to be an effort my some paleos to produce super sized marine reptiles to fit the bill. And perhaps dino size envy, there certainly were sauropods of 100 tonnes and maybe even more than that back in ye Mesozoic, where are the ichthyosaurs et al to compare? After all they are buoyed by water and whales got as big although that is pretty much limited to the late Pliocene-Pleistocene. And there is the new culture of why bother to go to the effort to produce carefully constructed profile-skeletals, just run some seemingly fancy-dandy calculations that will improve one's chances of getting tenure and we end up with Triassic basal ichthyosaur and basal whale masses over estimated many fold. One person has labeled my methodology old fashioned. As though that matters. What is important is that it is reasonably accurate. At least my work has been suppressing claims of megamasses in the technical literature, and the Attenborough documentary on the new giant Brit pliosaur did not even mention its mass as I recall. 

Cultural issues certainly contaminate paleo. As per the intense resistance to hot blooded dinosaurs spawning feathery birds and land loving sauropods and hadrosaurs and social dinosaurs back in the day. I got denounced for two decades for putting feathers on dinosaurs. Then there is the near cult status of T. rex. In 2013 when Peter Larson showed that Bloody Mary has hands larger than those of adult Tyrannosaurus it should have been atomically presumed that the former was not a juvenile of the latter because appendage atrophy does not happen in amniotes, Gorgosaurus and Tarbosaurus included. Instead that was ignored including in the supposed Carr 2020 masterpiece. Now that Longrich and Saitta have shown this is also true of Petey and another specimens (also Jodi) that all eutywrannosaurs from the Hell Creek etc are T, rex hypothesis is disproven. Likewise Brown et al. in 2015 found not a single example of a reptile species reducing maxillary/dentary tooth count as it grew up, the same is true of Grogosaurus and Tarbosaurus. So all the small tyrannosaurs from the Hell Creek etc. with more teeth than adult Tyrannosaurus cannot be its juveniles (those with the same number of teeth are its actual juveniles). In Carr 2020 the Brown et al. paper was misrepresented to back his idea that all eutyrannosurs in the Hell Creek region are T. rex, with the invention that they underwent a metamorphosis not observed in any other amniotes. The small eutyrannosaurus with big hands and lots of teeth are not even tyrannosaurids, they are basal eutyrannosaur dryptosaur relatives that migrated west across the new land bridge reuniting North American and were doing a good job competing with the scarcer juvenile Tyrannosauurus burdened with their less gracile proportions and whimpy armlets. 

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[marcello perillo]

On the matter of I.severnensis is to note some factors that may need to be remembered: 

1) S.sikanniensis is way more complete, known from an articulated skeleton and reported to a 20/21 m length; therefore ichthyosaurs that reached over 15 m in size in the Late Triassic are not unsurprising. 

On the other hand only a single species reaching this size would appear to be quite strange. Cetaceans and Sauropods reach giant sizes with multiple species and genera speciating while maintaining the huge dimensions. 

Saying that there were no further ichthyosaurs and that they could not reach larger sizes than the one shown by S.sikanniensis, would require support from a perfect understanding of the physiology of these animals and a complete fossil record documenting forms through the entire Late Triassic. 

2) Although a good question, the one regarding the lack of fossils of giant ichthyosaurs, the recent years have been full of discoveries from Rhaetian deposit, albeit fragmented. In the specific case of the Severn area, the first finds are from the 19th century and there is a hiatus of two centuries before a series of finds that was uncovered in the last years (3 surangulars one after the other, the 2 specimens for I.severnensis and the other surangular mentioned but not described in the 2024 paper). We can also mention the Kossen finds. Giant vertebrae and fragments of ribs are relatively common as well. My conclusion is that, rather than a genuine lack of giant ichthyosaurs being recorded in the fossil record, we are witnessing a moment in which the right spots are being exposed right now, (e.g. on the english coast) and that the probability of recognition and recovery of the fossils is increasing thanks to the awareness of fossil collectors. 

3) Saying that giant ichthyosaurs couldn't exist because blue whale sized cetaceans appeared only in the last few millions of years is circular reasoning, and is not a strong argument for understanding the actual evidence of the fossil record. If giant remains are found through the entire Late Triassic, even with hiatuses, there must have been the right conditions for them to evolve. 

4) the estimates were done with a selection of logically chosen comparable material and with the current knowledge of the research community. 

If any other competing estimation can be undertaken on the material, it would be an important aid in testing and discussing the results of the study, as it is supposed to be for the progress of our scientific understanding. 

Said so, the finds of the last 2 centuries show that the existence of giant ichthyosaurs in the Rhaetian does not really need to be demonstrated anymore and that there have been multiple species/genera like nowadays cetaceans reaching over 20m sizes ( many of which still need to be discovered by speciation logic). This has important implications on their role in the trophic communities, their phisiology and on the impact of the Tr-Jr mass extinction, rather than being a challenge between fishermen for the largest catch and as researchers we should focus on that.

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[Jura]

Has there been any study on estimating the nutritional content of ammonites? Mesozoic seas were so vastly different from extant seas that I wouldn't be surprised if these ammonite-dominated ecosystems were a rich source of nutrients for the marine life at the time.

Cheers,

Jason

[marcello perillo]

Not sure about that, but lunge feeding on shoals of adult ammonites seems dangerous for the amount of shells intaken (this doesn't exclude the possibility of strong digestive acids). On the other hand growing larvae could have represented a huge source of biomass. I saw the bundles of eggs from jurassic specimens in the Etches collection on UK that would suggest that at least in some Jr ammonites eggs were not dispersed in water but carried within the body... but larvae couldn't be carried around so easily so they must have represented a huge part of the nekton

Cheers,

Marcello 

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[Gregory Paul]

Unnamed genus (it is NOT Shonisaurus NOR Shastasaurus) sikanniensis TMP 94.378.2 is NOT 20/21 m long. The quarry map in the original JVP publication (can see it here -- http://markwitton-com.blogspot.com/2020/04/) starts at 4 m and ends at 21 m, so that is 17 m, do the subtraction -- people have been missing that one for years as they endlessly auto repeat the 21 m value without bothering to check the quarry map or do a skeletal, which is nonscientific malpractice. Add a little for the missing snout (I will bet the m indicators started at 4 at the frontmost end of the preserved skull because they had been looking for the rostrum another few meters as they expanded the quarry in the effort). I am the only person to do a scientific skeletal restoration, in my Princeton sea reptiles field guide p 53 scale bar provided, and it is 17-18 m depending on snout length. As noted in the original description the ribcage was shallow (the ribs look badly beat up, so not certain how long they were). Volumetric model recovers in the area of 16 tonnes. There is no actual evidence that the Ichthyotitan surangulars are from animals with longer jaws than ?. sikanniensis or Shonisaurus which was also ~16 tonnes. The length of the surangular varies from a third of the lower jaw length to two thirds in ichthyosaurs, so it is a very poor size indicator. In the Lomax et al. paper they restore the new surangular in a manner that may exaggerate its length, and use two minor markers to scale up its size from a much more derived, smaller, tunniform ichthyosaur which is not going to produce reliable results. Making it all worse is that we have no real idea how long the mandible of TMP 94.378.2 is, it missing up to half its length. How is this to be compared to the jaw bones of Ichthyotitan? Not doable.  

    My field guide is now 2 years old, is out of an academic press, and is the most extensive set of marine reptile profile-skeletals and estimated masses yet produced. It directly addresses and refutes the way over inflated masses by Sanders, Lomax and others, none of which is actually based on volumetric models of the key specimens (including TMP 94.378.2, UCMP 9950). Yet no one that continues to present the myth of super sized Triassic ichthyosaurs has cited that book. Why is that? Because you are not aware of it which is not paying attention to the scholarly literature? Or because it refutes the myth and folks do not wish to deal with that? I have noticed that the exaggerated mass estimates at least are not being presented, I suspect because of the field guide. Perhaps Perillo can enlighten us on this particular issue -- do your know about the book, and if so why is it not cited and the issues it raises addressed? 

Perillo says that in needs to be "remembered"  that TMP 94.378.2 is 20/21 m long. No, science does not work on remembering data, that is casual autopilot thinking that gets us into trouble when we (incl me) commonly do it. Proper science operates on the due diligence of checking the data, not just repeating it yet again. I suspect that when the JVP paper on TMP 94.378.2 was being written up the authors had so gotten that impressive figure in their their heads that it was 21 m long, and said so in the text even though their own quarry map shows it is about 4 m less than that, and they failed to do their due diligence of producing a skeletal drawing to be sure of its dimensions, and the reviewers did not do their due diligence of checking the claim which is easy enough just look at the quarry map and thus a false legend is born, and those who cite the paper and have a thing for super ichthyosaurs don't diligently check and keep repeating it, and this a myth is sustained and blown way out of proportion to somehow we have fin-blue whale herps back in the Triassic the evolutionary rapidity of which should have caused the proponents to wonder if their mass results were valid and take a look at that quarry map. 

    So. If any wish to continue to contend that any known sea reptile fossil exceeded 20 tonnes, then you MUST get off your paleo butts and take the time and care to produce and publish an accurate profile-skeletal of TMP 94.378.2 based on the actual measurements of the quarry map and the scale bars in the JVP description of the elements, produce a volumetric model, and go from there. Why has no one done so except for me? Because most paleos these days are not interested in doing actual anatomy to actually see how big a specimen is, they prefer mathematical calculations often based on bad original data they do not bother to check out (this evasion of whole animal anatomy is a problem in modern biology in general). The same applies to the nonsense that the "C." youngorum holotype was 45 tonnes. We have good old UCMP 9950 which is complete and articulated except for the distal tail. It is a skinny thing and its mass was less than 3 tonnes on a good day. Scale it up to the youngorum skull and the mass is around 10 tonnes, a forth that estimated. So do one of the following. If you are not willing to produce high grade profile-skeletals and volumetric models and from those mass estimates, then cease making size claims. Or, produce and publish such restorations. It is not that hard to do, these are technical illustrations based on articulating bones, there is no actual art to it. Reproduce the Ichthyotitan surganulars at the same scale next to the skeletals for TMP 94.378.2 and Shonisaurus with a scale bar thrown in. If doing that results in sizes over 20 tonnes that could be interesting. Or if they show the beasts do not show compelling evidence of being over 20 tonnes then say so and revise your past work. It's called science. Same for UCMP 9950 and the "C." youngorum holotype. 

Is that so hard to do? 

There was very recently a similar marine paleodisaster of hyper size exaggeration of a basal sea going animal, when the description of Perucetus used untested speculative calculations to bizarrely claim it was 85-340 tonnes, resulting in international headlines that a whale as big as blues had evolved in the Eocene just a few million years after the appearance of flippered cetaceans. That being biologically impossible., Of course they did not bother to measure the volume of their own crude skeletal which has a mass of just ~60 tonnes. A paper then came out that easily debunked the obviously Perucetus paper. Here is the twisted irony. Larramendi and I submitted a paper that is nearly identical to the latter paper. Ours was rejected by reviewers who were incompetent nitwits who have no idea how to estimate the sizes of extinct animals (one reviewer actually accused us of being sexist for noting that female blue whales are the largest not making that up). So an inane paper made it past peer review and got international coverage, our entirely scientific reply was rejected, and another set of reviewers with functioning neural networks OKed a paper that is much the same as ours and got less coverage. By opinion of review continues to plunge further into the mine pit. (The published rebuttal came out just before we got notice of the rejection so at least we did not lose priority due to the wacky reviews). Likewise my paper on the actual appearance of the blue whale based on the first correct profile-skeletal (which refutes the mounted skeletons that do not match photos of the living animals) kept getting rejected so I finally said to hell with it and posted it on BioRxiv (https://www.biorxiv.org/content/10.1101/2022.08.28.505602v1 where is has gotten about 1K views). 

Getting back to the Triassic, a series of papers have gotten past peer review that make those exciting headlines based on the entirely spurious claim that TMP 94.378.2 is 21 m long when doing the proper scientific due diligence of checking the quarry map shows it is 17 m. I have submitted my paper that among other items notes that is patently not true and it has been rejected. Getting back to the query that lead to this thread, very probably because of the super ichthyosaur cult that is not happy about their mismeasurements being exposed as false. One reviewer said my mass estimation method is obsolete. No, profile skeletals will never be obsolete, and a system that produces results as accurate or superior to the others is not out dated either. 

Perillo tries to claim that I am stupid enough to argue that because super whales did not evolve until the Pleistocene that that refutes the existence of super sea reptiles. Apparently Perillo has trouble understanding English, I was merely noting that such titanic cetaceans are limited to a few million years (too recent to be found as fossils) I made no further claims. It is possible that the special ocean conditions of the ice age allowed the only actual known appearance of extremely large sea creatures, but that is not my hypothesis although it sounds good to me. 

As I have noted in the field guide, sea reptiles may well have gotten to the area of 30 tonnes, but there is no actual fossil evidence to date of specimens over 20, and the absence of larger remains after a couple of centuries of looking leaves the possibility of any over 30 some tonnes low.

As I have noted before, way way back in the 1980s I realized that no one was restoring the anatomy or masses of dinosaurs, so I established the scientific standards for doing so via rigorously produced profile-skeletals (scanning mounted skeletons can also work if the mount is anatomically correct). Yet here we are well into the 2000s with researchers, most of them working on marine tetrapods, sailing right past the rigorous methods and using floating calculations to arrive as mass estimates that are patently absurd and way out of line with the actual fossil remains. What the heck is going on here? If you are not willing to do the work of producing skeletals or scanning mounts, then get out of the business of mass estimation of very large creatures and leave it up to those willing to do the work. 

So Perillo and company. Actually want to produce some profile-skeletals to back up your claims that it was 21 m long? I am not holding my breath, but it would be interesting to see what you come up with if you do it. And have you ever looked at the quarry map and read the measurements. Want to acknowledge it is actually 17 m, not 21? 

And stop ignoring my book. 

GSPaul

    

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Ichthyotitan, new giant ichthyosaur from Late Triassic of UK + large ich...

ed 

[Russell Engelman]

I will say I've had other colleagues tell me they were unable to replicate the proposed lengths of 20-21 m for Shastasaurus sikanniensis based on the figures in the JVP paper, as well as trying to compare the figured material with elements of Shonisaurus popularis. However, because these colleagues weren't marine reptile specialists they didn't consider it worthwhile to make a big deal out of it. There are actually quite a few dubious size estimates in paleontology.

Russell