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PWNZ3R-Dragon In reply to Rimasuchus [2017-12-25 17:32:35 +0000 UTC]

First, discrepancies in body:tail ratios are the result of vertebrae count, rather than scaling. To recap in my description:

"Vertebrae - Bones restored from pictured elements from various specimens. Atlas from IRSNB R 300. Axis from IRSNB R26. Cervicals restored from NHMM 006696. Dorsals restored from IRSNB 1624, NHMM 006696 and S34-S77. Tail mostly restored from S34-S77 to fit UCMP 61221. Vertebrae count based on details listed for M. hoffmannii and M. conodon, Russell 1967 and Ikejiri and Lucas, 2015."

Mosasaurus's vertebral series suggest a proportionally longer back and shorter tail stock than is conventionally restored based on other mosasaurs. Up to 38 dorsals in Mosasaurus, with evidence for only 9 pygals and 21 intermediate caudals (according to Ikejiri and Lucas 2015, Russell 1967, and Lingham-Soliar 1995). I could actually match with Schulp's ratio estimations by following the estimations in vertebra arrangement for M. lemonnieri provided by Ikejiri (there's a fairly wide margin of estimation there) ie. shortening the back by 6 dorsals and elongating the tail by 6 pygals, which would actually bring me pretty close to the mark on Lindgren's chart as well. But I opted otherwise in favour of what was provided with what was listed for "M. maximus" since it's a junior synonym of M. hoffmannii, even if it meant digressing relatively slightly from Lindgren 2011, or Schulp's percentage estimate. 

I scaled the skull size and limb size relative to vertebrae via pics and scalebars provided by Street and Caldwell's redescription of the species. IRSNB R26, NHMM 006696 and the holotype were key specimens here since they each had skull parts, limb parts and vertebrae to work from. From there, I used available overlapping bones from other specimens to scale in the remaining parts.

I have already addressed what Lindgren suggested about my Mosasaurus's tail fluke's soft tissue as part of the current version, which to refer to Prognathodon's soft tissue data (which it appears you haven't done yet), although he said he was unable to provide anything specific beyond that. Everhart, on the other hand, seemed okay with the current restoration when I contacted him a while back via facebook, save for minor edits to the rib cage and eye socket (again, since updated). I'm awaiting feedback from Caldwell about it as well, though I suspect I may have to wait a while for further feedback from him or Street on the matter. Konishi as well. I have not personally contacted Schulp yet, but that's a conversation I'd rather have personally rather than have someone else go behind my back about it.

But before we discuss my Mosasaurus skeletal further (by that I mean, have it posted on a forum with intent to publicly eviscerate without even bothering to contact me directly about any concerns they had, which almost seems like a personal grudge is involved for god knows why), I'm curious about your own silhouette. How did you end up with a Mosasaurus with such a small skull, limbs, a massive domed back and general proportions completely unlike any other mosasaur discovered thus far? What was your method? Did you scale all the individual bones together via images, scale bars, measurements and data provided by the literature and infer from its most closely related taxa? Or did you rely almost exclusively on vague estimates and ratios?

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Rimasuchus In reply to PWNZ3R-Dragon [2017-12-26 10:55:34 +0000 UTC]

Tail length is conditioned not only by number of vertebrae. Reconstructed by Lindgren et al. (2007) composite specimen of Plotosaurus bennisoni (based on CIT 2750, 2755, 2756, UCMP 32778, 126284, 152554 and 152643) have 37 dorsal, 30 pygal and 6 intermediate caudal vertebrae - about same total caudal and precaudal vertebrae number as your Mosasaurus hoffmanni reconstruction. But Lindgren's Plotosaurus have longer tail due to lenght of pygals and intermediate caudals, while on your M. hoffmanni reconstruction these vertebrae are rather short (as in Moanasaurus S34-S77). A. Schulp personally worked with NHMM 006696 material and I think (and M. Everhart too) that we must be informed by material of this autor about reconstructions of M. hoffmanni skeleton. Lindgren et al. (2011) figure shows proportions of UCMP 61221 column - Mosasaurus sp. with 8 pygals and 21 intermediate caudals (as in M. condon), not partial column of DMNH 21006 or M. lemonnieri. You also can see on reconstruction of M. hoffmanni by Stefan Vink approximately same ratio of pygal vertebrae lengths as in Plotosaurus.
And I still note that no pygals that articulated with intermediate caudals in M. "maximus". 9 or 10 (Ikejiri & Lucas, 2015; restored from fig. 2 in Langston, 1966) is a number of preserved pygals (similar number of preserved pygals indicated for IRSNB R26 by Lingham-Soliar, 1995). Also there is no data for number of intermediate caudals vertebrae in M. hoffmann/M. "maximus" and possible number of dorsal vertebrae can freely vary from 32 to 38. This make these based on Mosasaurus condon and UCMP 61221 tail lenght estimates quite conservative.

I'm sorry if my old friend used my email correspondence with M. Everhart, J. Lindgren and A. Sculpt against your reconstruction on forum. I really discussed your reconstruction and reconstruction by Stefan Vink with these scientists, but only to work with my own reconstruction. However, this correspondence was already after last update of your reconstruction and commentaries of scientists will probably be useful for your future work.

To create my M. hoffmanni silhouette I make composite specimen from scaled fragments of BMNH 42929, MNHN AC 9648, NHMM 006696, IRSNB 1624, R26, R12 and NHMM 1993024, as well as proportions of composite Plotosaurus bennisoni, Mosasaurus missouriensis TMP 2008.036.0001 and tail of Mosasaurus sp. UCMP 61221. I use similar method, but took BMNH 42929 as basis, because this specimen have three articulated cervical vertebrae of known position & frontal that allows to estimate skull lenght, while position of NHMM 006696 vertebrae unfortunately unknown and A. Sculp could not confirm the previously mentioned 144 cm skull length.
Precaudal part of column based on TMP 2008.036.0001 proportions, BMNH 42929 cervicals, MNHN AC 9648 cervicals from unknown position, NHMM 006696 cervicals and dorsals from unknown position, IRSNB R 299 dorsals from unknown position (actually, I took only shape of vertebrae from unknown position). Tail based on Lingren et al. figure for UCMP 61221 and reconstruction of this specimen tail from paper, but also with one additional pygal. Forelimb based on IRSNB R26, R12 and NHMM 1993024 (scale based on IRSNB R12 humerus size to lower jaw length and proportions of NHMM 1993024), hindlimb scaled to forelimb from Stefan Vink model. But there were some difficulties with reconstruction of rib cage based on material by Lingham Soliar (1995) for Mr R. Garcet's specimen of M. hoffmanni (scale based on height of vertebrae and height of reconstructed rib cage give "shape of massive Clidastes", as suggested by M. Everhart, but not by A. Sculp and J. Lindgren), and I took rib cage of Plotosaurus giving it a more barrel-like shape and massive ribs as described for M. hoffmanni by Lingham Soliar and reconstructed by Stefan Vink.
Final composite specimen was too graphical-curve due to different color and quality of specimens in papers figures (I just photoshoped many fragments on one list, not draw from scratch) and I replaced it with silhouette. In general I get simular Mosasaurus hoffmanni skeletal as Stefan Vink, but with smaller paddles. I estimate ~15.4 m TL for CCMGE 10/2469 with 32 dorsal vertebrae (same number of vertebrae and proportions as in model by Stefan Vink, max skull lenght [lower jaw] - TL ratio close to 1:9) and ~17 m TL with 38 dorsal vertebrae (max skull lenght - TL ratio close to 1:10, as in Plotosaurus), but in both cases tail took 120% of precaudal column lenght as in UCMP 61221 (and one additional pygal), while pygals number as in M. lemonnieri can give longer tail. Yes, massive domed back is a defect that I get when covered skeleton with soft tissues, I fixed it on my computer a few weeks ago, but not on deviantart. If you are interested, I can give you all my measurements of M. hoffmanni specimens.

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PWNZ3R-Dragon In reply to Rimasuchus [2017-12-26 21:27:59 +0000 UTC]

God I hate walls of text. So difficult to respond to text walls in an organised manner...

Firstly, 36 caudal vertebrae is not "about the same" as 30 caudals. That's already a 20% increase in the tail stock length. That's pretty substantial as it is. While on the subject of vertebra count, 9 pygals has been preserved multiple times (twice in M. maximus - TMM 313 and NJSM 1105321; once in M. hoffmannii - IRSNB R26; once again in M. sp - FMNH P26956), 21 intermediates came from M. conodon (Russell 1967), Mosasaurus sp. UCMP 61221 (Lindgren et al. 2011) and Mosasaurus sp. SDSM 452 (Ikejiri & Lucas 2015), and the terminals came from UCMP 61221 again. The current caudal vertebrae count is likely a better fit for the species than any alternatives. As for dorsal vertebrae, I went with 38 based on the fact that multiple specimens of the genus are either known to have 38 vertebrae, or regularly quoted at having at least 30 with some vertebrae missing. 38 seemed like the most reasonable option to represent a complete dorsal series for the genus. As I have said before, I could use the margins of error in vertebrae count listed for M. lemonnieri to extend the tail further or shorten the back, but I'm not convinced that's necessary. 

Second, while I have thus far been unable to actually find photographs of Plotosaurus's pygals to compare, Moanasaurus's pygals were almost identical in shape to that of "M. maximus"  ANSP 8529 (taking into account that one is only available in lateral, and the other in dorsal views), so relative centrum length does not seem to be an issue here either. Not to mention that while the phylogeny of Plotosaurus puts it deep within Mosasaurus (yet oddly remains separate), it's worth noting that it's not exactly the best representative for the genus in terms of general morphology. It has a lot of really weird things going on not seen throughout Mosasaurus proper, in that it's far more "ichthyosaur-ish" than its relatives. Which is why I avoided using Plotosaurus as a reference in the first place. Moanasaurus, or what bits and bobs of it we have, was simply a better fit morphologically and likely is a synonym of Mosasaurus anyway. If you have Plotosaurus pygal photos, and ideally a photo of NHMM 006696's pygal in lateral view, I'd very much like to see them for comparison's sake. Truth be told, I'm not exactly sure what you expect me to do at this point otherwise.

I'd be very curious to see those measurements. Vertebrae count aside, the size of the skull and flippers relative to body size seem astonishingly small and I personally think that's a more concerning difference between our restorations than the position of the tail base along the vertebral series (since it's pretty clear that's the result of differing views on what the "average" Mosasaurus vertebrae count should be). I made it a point to avoid estimated head:body or dorsal:caudal length ratios in favour of letting scale bars provided in papers do the talking, in case of any error margins as a result of vague estimations (a 1:10 head-body ratio is actually really rare in mosasaurs - Prognathodon overtoni and Tylosaurus sit somewhere around the 1:7 mark, and Platecarpus sits around 1:8, and Lindgren's Plotosaurus is the smallest I'm aware of with 1:9, for instance). 

When you created your silhouette, did you by any chance draw it around scaled and articulated bones, or was it an estimation based on the measurements only? It might be easier to clear up discrepancies if you had the bones scaled and posed in yours, to see what's what. From the looks of it, it looks like the head and flippers are scaled to each other similarly to mine, but then both were scaled down together to fit the 1:10 head-body ratio, while I just went with what Street's and Caldwell's scalebars indicated. Though I have no idea what effect this has on the scapulocoracoid or pelvis in your restoration, especially since the pectoral girdle is noted to be quite large, especially once you add in the cartilage expansions. 

Also, I made it a point to try and avoid referring to the skeletal drawings or renders of others out there (not that there's many) for things like proportions and stuff for the same reason (not to disrespect Vink's skeletal render or anything, I needed to be sure I didn't pick up anyone else's possible errors on top of my own possible errors along the way). 

I can't say I'm particularly impressed by people dumping my skeletal work on experts behind my back without actually forwarding me the feedback directly. It's even worse that I'm now apparently getting contradictory advice from the same experts I've had direct contact with that otherwise approved of my work. And then your old friend opted to, rather than talk to me about any of these concerns and be helpful, chose to to make an attempt at utterly humiliating me and my work for no discernible reason. That was pretty mean on his part.

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Rimasuchus In reply to PWNZ3R-Dragon [2018-01-06 09:38:10 +0000 UTC]

Recently we contacted with Anne Sculp on e-mail and I got more details about NHMM 006696. I do not know how you scale column of NHMM 006696 based on S34-S77 measurements, because position of NHMM 006696 vertebraes is unknown. Also, figures from papers with scale bars are not very reliable source in comparison with actual measurements. Reconstruction from maastricht museum that built by Hans Brinkerink/Vista Natura based on measurements of NHMM 006696 material and will be the best source for NHMM 006696 bone proportions, because no real measurements of this specimen have been published in literature. Mounted skeleton has ~1:8,8 head-body ratio based on skeletal by Stefan Vink, that based on this skeleton and consultations by Anne Sculp about this reconstruction, but also have incorrect number of vertebrae (mounted skeleton created before Lingham-Soliar papers) as 4 cervical, 32 dorsals, 4 pygals, 21-43 intermediate caudals and 40-42 terminal caudas:
 
 
 
 
If we change number of vertebrae to 7 cervicals, 38-39 dorsals (38 built of 17 thoracic and 21 lumbars, 39 built of 18 thoracic and 21 lumbars), at least 9 pygals, about
 21 intermediate caudals and about 50 terminal caudals, preserving all bone proportions, then we get a 1:10 or 1:9 head-body ratio, as originally stated by Russell for M. "maximus".

Another question is size of limbs. It seems to me that it should be smaller than in skeletal reconstruction by Stefan Vink.

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Rimasuchus In reply to Rimasuchus [2018-01-12 07:54:26 +0000 UTC]

"but also have incorrect number of vertebrae (mounted skeleton created before Lingham-Soliar papers) as 4 cervical, 32 dorsals, 4 pygals, 21-43 intermediate caudals and 40-42 terminal caudas"

Misprint. Of course, mounted skeleton has a 8 cervical, 32 dorsals, 4 pygals, 21-23 intermediate caudals and 40-42 terminal caudas.

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Rimasuchus In reply to PWNZ3R-Dragon [2017-12-27 15:35:41 +0000 UTC]

In general 6 caudal vertebrae give only 10-15% in total tail lenght (moreover, do not forget that plotosaurus has relatively short intermediates). This corresponds with that Plotosaurus has slightly longer tail than UCMP 61221 in comparison with total column length, as you can see in Lindgren (2011) figure. I agree with number of vertebrae, but as I say is a fairly conventional number based on close relatives and specimens without articulated caudal part of column.

Plotosaurus pygals has simular centrum height-width ratio as ANSP 8529 and S34-S77 (see Lindgren et al., 2008; but is a reconstruction, not photo). I think tail lenght in this case depends on proportional pygals size. In Plotosaurus pygals together with posteriormost dorsals is largest centra in all axial skeleton. Unfortunately, I do not have photos of NHMM 006696 pygals.

I scale scapula, coracoid and pelvic girdle from IRSNB R26, NHMM 006696 and model by Stefan Vink. About scaling of limbs see measurements below for NHMM 1993024 and IRSNB R12. Skull size based on BMNH 42929 cervicals. About proportions, Lindgren's Plotosaurus have ~1:9.55 lower jaw-Tl ratio, Clidastes normal proportions is approximately 1:8.2 but varies in species and even in specimens. It seems common for Mosasaurinae to have smaller heads in relation to total lenght than in Tylosaurinaes, with Prognatohodon overtoni (and very likely other Prognathodon species) as exception.

My measurements (unfortunately, not all are preserved):

Holotype (MNHN AC 9648)
Lower jaw: 135 см.
Cervical vertebrae height: 25.42 cm.
Quadrate height: 16.55 см.
Quadrate width: 10 см.
Source: Street, H.P., and Caldwell, M.W., (2016) Rediagnosis and redescription of Mosasaurus hoffmannii (Squamata: Mosasauridae) and an assessment of species assigned to the genus Mosasaurus.

Bemelse Mosasaur (NHMM 006696)
Cervical vertebrae height (incomplete) - 20 cm.
Cervical vertebrae lenght - 11.02 cm.
Dorsal vertebrae height (incomplete) - 17.8 cm.
Dorsal vertebrae lenght - 11.53 cm.
Terminal caudal vertebrae lenght - 6.93 cm.
Quadrate height (pathological): 18.3 cm.
Quadrate width (pathologica): 13.78 cm.
Max skull lenght (?): 144 cm.
Source:  Anne S. Schulp, Geert H.I.M. Walenkamp, Paul A.M. Hofman, Yvonne Stuip & Bruce M. Rothschild (2006) Chronic bone infection in the jaw of Mosasaurus hoffmanni (Squamata); Street, H.P., and Caldwell, M.W., (2016) Rediagnosis and redescription of Mosasaurus hoffmannii (Squamata: Mosasauridae) and an assessment of species assigned to the genus Mosasaurus.

NHMM 1993024
Humerus: 11.85 cm.
Paddle: 60.74 cm.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni.

BMNH 42929
Frontal: 36.36 см.
Cervical vertebrae (three articulated): 28.125 cm.
V1+V2. H=16.63 cm, L=9.46 cm; V3 H=17.5 cm, L=10.24 cm; V4 H=16.87 cm, L=8.43 cm.
Lower jaw (based on Frontal): 119.05 cm.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni.

IRSNB R12
Lower jaw: 110.37 cm.
Humerus: 9.5 cm.
Paddle (based on NHMM 1993024): 48.69 cm.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni.

CCMGE 10/2469 (PRM 2546)
Lower jaw: 171 cm.
Dorsal skull lenght: ~150 cm.
Source: D. V. Grigoriev (2014), Giant Mosasaurus hoffmanni (Squamata, Mosasauridae) from the Late Cretaceous (Maastrichtian) of Penza, Russia.

IRSNB R26
Axis: 19.33 см.
Humerus: 11.25 см.
Atlas-axis complex height: 27.14 сm.
Atlas-axis complex width: 20 сm.
Quadrate height: 12.95 сm.
Quadrate width: 9.1 сm.
Lower jaw: 150 сm.
Dorsal skull lenght: ~130 сm.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni; Street, H.P., and Caldwell, M.W., (2016) Rediagnosis and redescription of Mosasaurus hoffmannii (Squamata: Mosasauridae) and an assessment of species assigned to the genus Mosasaurus.

NHMM 009002
Lower jaw: 160 см.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni.

NJSM 11053
Lower jaw: 123 cm.
Quadrate height: 16.7 cm.
Quadrate width: 9.83 cm.
Source: Eric W. A. Mulder (1999) Transatlantic latest Cretaceous mosasaurs (Reptilia, Lacertilia) from the Maastrichtian type area and New Jersey.

NHMM 603092
Quadrate height: 26.15 cm.
Quadrate width: 16.3 сm.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni.

TSMHN 11252
Humerus: 17.41 cm.
Source: T. Lingham-Soliar (1995) Anatomy and functional morphology of the largest marine reptile known, Mosasaurus hoffmanni.

Perhaps some of them will be useful to you.

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PWNZ3R-Dragon In reply to Rimasuchus [2018-01-07 20:28:11 +0000 UTC]

I'm going to focus on the measurements only in this post, partly because you place too much trust in skeletals that don't even agree with your own end result, partly because eyeballing photos of skeletal mounts to get measurements is a bad idea on so many levels, but mostly because there's some glaring problems with what you've sent me:

Holotype (MNHN AC 9648):
I don't know how you got any of these measurements from that paper. There are NO measurements quoted in that paper for this specimen. Furthermore, you've provided a quadrate, a cervical vertebra and a lower jaw. The holotype is known from a complete but disarticulated skull, two cervical vertebra and a femur. The paper provides images for the specimen in matrix, and in isolation the maxilla, jugal, squamosal, quadrate, pterygoid, intramandibular joint, one cervical (which I've interpreted as a C5) in posterior view, and the left femur. And there are no numbers provided by the paper you cited for these bones. What's more, the femur itself was crucial for scaling the hind flipper to the skull and the rest of the body. As far as I can tell, you've basically pulled those numbers out of your ass (skull size ratios aside, your measurements would actually result in the holotype's skull having a substantial underbite by two or three tooth places if you assume the cranium of Street's and Caldwell's composite reconstruction is otherwise reliable).

Bemelse Mosasaur (NHMM 006696):
Similarly with the holotype's data, Caldwell's and Street's paper do not provide measurements for this specimen. Only pictures of one cervical (which I've interpreted as a C4), one dorsal (which I've interpreted as a posterior thoracic) and one caudal (a terminal). It did provide images of a tibia, coracoid and premaxilla too. But again. No measurements in the paper. The paper on Mosasaurus's bone infection doesn't even address vertebra at all, and the only measurement it provides is for the 1.4m skull length estimate. Again, these numbers would have to have come out of your ass. Notably your measurements of the cervical and dorsal don't even match the bones themselves (ironically, for their heights, your measurements SHORTEN the centra than photos would otherwise suggest). Yet weirdly, when you compare the quadrate to relative vertebra heights, mine actually nails it already. It's even funnier that you've come to me with measurements for this specimen, when you said yourself since posting it that no measurements exist in literature.

NHMM 1993024:
This measurement isn't all that useful to me here. The humerus and paddle alone aren't able to provide a scaling reference in relation to the rest of the animal, and I used different specimens (R26 for the humerus, R299 for the radius, and RMDRC 14-015 to fill in the rest of the paddle). But again, Lingham-Soliar never provides numerical measurements for the specimen, so your number is once again, made up. Does your paddle measurement include or exclude the humerus? It's pretty close if it includes the humerus, but is vastly oversized otherwise.

BMNH 42929:
Running trend here, no measurements actually provided by the source paper. Not only that, it only has three cervicals (mid cervicals - they aren't a V1 and V2, which would be the atlas and axis, so the three preserved are interpreted in my restoration as a V3, V4 and V5) presented in the paper, along with some dorsal cranial data. You've not only made up measurements, you've made up a non existent vertebra. And yet, and YET, rather than suggest a really small skull, they fall very close to my skeletal's proportions. You played yourself here, mate.

IRSNB R12:
Again, paper doesn't cite measurements. Where ARE you getting these from?! Also, this measurement would suggest that R12 has a skull 1.5 times BIGGER relative to body size than my skeletal. I really cannot say more than that.

CCMGE 10/2469 (PRM 2546):
Can't really do much with this. The lower jaw measurement is the only measurement thus far cited in its respective paper. But it has nothing else on that specimen's body to compare with. It's only relevant because it's large.

IRSNB R26:
Again, no actual numbers were presented in the paper. But this is where I'm strongly convinced you've made a mistake. Because your measurements for the axis and atlas require the vertebrae to DOUBLE in size from what they're currently at in my skeletal. Your quadrate measurement would also require my skull to increase in size substantially as well, resulting in extremely small flippers. The cervical and quadrate measurements you've made up already disagree with your own measurements for NHMM 006696 and BMNH 42929. Not only that, again, you're looking at a skull with serious underbite issues (like, if you increase the cranium size to fit the quadrate height relative to humerus length in my skeletal to match your measurement here, you'd need to double that increase for the lower jaw).

NJSM 11053
Never even referred to this specimen. Not seen it, or the paper it came from, so I can't comment on it.

The remaining two measurements, I can't do anything with since they lack other bones to compare. But again, the papers you've cited do not provide those numbers for those bones at all.

Overall, your measurements are seriously inconsistent with each other, and don't even follow your end result, or anything provided in the literature. They do not exist. At all. Anywhere. At this point, I'm starting to think you're trolling me and that I just wasted a lot of time following up what seem to be completely arbitrary numbers.

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Rimasuchus In reply to PWNZ3R-Dragon [2018-01-08 10:50:07 +0000 UTC]

All my measurements made on paper figures, as well as your measurements. If you look at the date of my comments, you can see that first comment was written later (after my personal correspondence with Anne Sculp), and just suggests other method of scaling, based on NHMM 006696 skeletal mount by Hans Brinkerink, than measurements from figures.

Holotype (MNHN AC 9648):
All measurements of cervical vertebrae and quadrate based on figures (fig. 17 and fig. 13 respectively) in Street & Caldwell (2016) paper. Lower jaw lenght measured from reconstruction in fig. 1.

Bemelse Mosasaur (NHMM 006696):
I know that my measurements do not correspond to skeletal, that based on NHMM 006696 skeletal mount. This is not my skeletal and it do not correspond to my Mosasaurus hoffmanni silhouette.
Cervical vertebrae, dorsal vertebrae, terminal caudal vertebrae measured from figures in Street & Caldwell (2016) paper. Quadrate measured from Sculp et al. (2006), but approximate length of skull mentioned in papper's text.

NHMM 1993024:
My measurement of total paddle length of this specimen includes humerus too. Forelimb size of other specimens based on humerus-paddle size ratio in NHMM 1993024 and further measurements of IRSNB R12 with ~1.1 m skull.

NHMM 1993024:
First preserved vertebra of this specimen looks like axis (V2) for me, according to morphology of roughened area and vertebral hypapophysis. In this case NHMM 1993024 has V2 (complex with V1), V3 and V4. As I can tell at your reconstruction with same lower jaw lenght V3 on ~30% smaller than NHMM 1993024 mid cervical.

IRSNB R12:
Lower jaw of this specimen measured from fig. 3, humerus from fig. 20, forelumb scaled from NHMM 1993024 (fig. 21). I'm really interested in our discrepancy in reconstruction of limbs size.

CCMGE 10/2469 (PRM 2546):
Oh sure. My measurements of this specimen based on reconstruction by Grigoriev (2014).

IRSNB R26:
Measurements of atlas-axis complex reconstruction of this specimen as well as all other my measurements of IRSNB R26 taken from figure 17 in Lingham-Soliar (1995) paper. Perhaps it seems to you that "in this case vertebrae should be larger", because this specimen actually has a ~1.5 m skull, not ~1.3 m as claimed by Bardet & Tunoglu, 2002 (see fig. 5 and reconstruction on fig. 4 in Lingham-Soliar paper). This specimen also has a proportionately very small quadrate in relation to skull size, if Lingham-Soliar (1995) did not make a mistake in fig. 12. You can personally measure bones from Lingham-Soliar (1995) paper figures, and make sure that I do not "trolling" you.

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PWNZ3R-Dragon In reply to Rimasuchus [2018-01-08 11:10:50 +0000 UTC]

So you used scale bars to create your own numbers, even though you've literally just said you found scale bars unreliable and that your measurements were better.

Are you for real?

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Rimasuchus In reply to PWNZ3R-Dragon [2018-01-08 18:06:12 +0000 UTC]

I did not say that "my measurements are better". But yes, all scales based on such figures (regardless of who made this measurements) unfortunately have some grain of salt. I do not want to "refute" or "eviscerate" your reconstruction, I just want to discuss it and help to improve it (if it's required after all).

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kirkseven In reply to Rimasuchus [2018-01-08 20:10:35 +0000 UTC]

''I do not want to "refute" or "eviscerate" your reconstruction''

You really do.. no need to fib about such things.

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AlternatePrehistory In reply to PWNZ3R-Dragon [2018-01-08 11:26:53 +0000 UTC]

LMAO

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PWNZ3R-Dragon In reply to mark0731 [2017-11-11 13:46:12 +0000 UTC]

That's because it's based on the tail fluke reconstruction for Mosasaurus sp. from Lindgren 2011, and not Tylosaurus. Not that Tylosaurus has soft tissue preserved anyway.

Gonna update it some point in the future to line up with what we see in Prognathodon's tail fluke. So we'll see what happens then.

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mark0731 In reply to PWNZ3R-Dragon [2017-11-12 14:18:11 +0000 UTC]

I didn't mean this as a critique, I just wanted to mention that it's strange to me.

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PWNZ3R-Dragon In reply to Corallianassa [2017-10-29 11:06:42 +0000 UTC]

Couldn't really say to be honest. Liodon's phylogeny is a mess as it is from what I can tell, so it's hard to infer relatives as a point of reference. "More basal than Prognathodon" is the closest I can find online.

But not all mosasaurines seem to be stubby monsters. Based off a couple of skeletal reconstructions I've seen, Clidastes seems to be more slender for its size, and Plotosaurus has an even larger chest, but a really slim skull than a similarly sized Mosasaurus.

But where Liodon fits on that spectrum, I have no idea.

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Corallianassa In reply to PWNZ3R-Dragon [2017-10-29 13:35:02 +0000 UTC]

Ok, thanks. It seems to fall between Clidastes and ´´Prognathodon kianda´´ on a recent cladogram, so I suspect it would be on the skinnier side.

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PWNZ3R-Dragon In reply to Vitor-Silva [2017-10-26 15:26:54 +0000 UTC]

That's awesome! What kind of Mosasaurus related project are you working on, if you don't mind my asking?

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Vitor-Silva In reply to PWNZ3R-Dragon [2017-10-26 22:04:01 +0000 UTC]

A model, but for a different proposal. A bad part is that I didn't suspected of such short tail at the time, so went with a "common" one xP

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PWNZ3R-Dragon In reply to Paleo-reptiles [2017-09-27 03:26:58 +0000 UTC]

Nah, I've done my part for the group.

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PCAwesomeness In reply to Kagansaurus [2017-08-28 02:15:46 +0000 UTC]

Yup! Same with Plesiosaurus and Ichthyosaurus!

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CJCroen In reply to PCAwesomeness [2018-04-15 05:13:04 +0000 UTC]

And pterosaurs!
(tbh, this is part of why it bothers me when people insist that those animals are dinosaurs--they were all identified long before we identified our first non-avian dino!)

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PCAwesomeness In reply to CJCroen [2018-04-15 14:07:59 +0000 UTC]

Only one, though.

(Pterodactylus)

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PWNZ3R-Dragon In reply to Kagansaurus [2017-08-28 00:12:53 +0000 UTC]

YUP.

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PCAwesomeness In reply to Yutyrannus [2017-08-28 02:16:15 +0000 UTC]

how about Plesiosaurus and Ichthyosaurus skeletal first these guys desperately need one

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Yutyrannus In reply to PCAwesomeness [2017-08-28 05:24:36 +0000 UTC]

To be honest, I'd rather see something known from better remains and that is more important to our understanding of those groups than just the genera the group is named for get a proper skeletal treatment (or a polycotylid...).

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PCAwesomeness In reply to Yutyrannus [2017-08-28 12:45:09 +0000 UTC]

Plesiosaurus and Ichthyosaurus are known from good remains; hell, Ichthyosaurus has even had soft tissue preserved!

As well as this, they were very important to science back then, and now, the only skeletals we have of them are...

A) distorted and without any flesh outline
B) not very rigorous at all

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PWNZ3R-Dragon In reply to PCAwesomeness [2017-08-29 22:27:28 +0000 UTC]

I am going to avoid Ichthyosaurus like the plague. Maybe I'll do something with fewer vertebrae next time...

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PCAwesomeness In reply to PWNZ3R-Dragon [2017-08-29 23:17:40 +0000 UTC]

How about Plesiosaurus?

Oh, wait; it also has a shit ton of vertebrae...

RIP in pieces

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PWNZ3R-Dragon In reply to Bestiarius [2017-08-09 01:36:49 +0000 UTC]

Honestly this was one of the reasons why I skipped out on the lips in this skeletal. Couldn't get it to look right because of how variable it was among modern monitor lizards, so drawing from any point of reference wasn't working for me. But yeah, it's extremely likely they had them, but given their marine adaptations, I reckon they'd have looked a little bit tighter to the bone, like the lips of cetaceans.

That being said, the nasal openings and the bone surrounding it doesn't seem as "scooped out" like in modern squamates either. So that may have some implications on the profile of the snout. Raised nostrils, perhaps? Or just something not as developed as in other lizard groups?

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