Dragons of the Deep: The Mega Ichthyosaurs

Secure your privacy with Surfshark! Enter coupon code VIVIDEN for an extra 4 months free at surfshark.deals/vividen
Receive free short stories by signing up here: forms.gle/GGGFqMfn1AgMZJaF9
Hector's Ichthyosaur speculative reconstruction by Diocles305 x.com/Diocles305
Music by Unicorn Heads.
The Mesozoic was terrifying, and ichthyosaurs were one of the biggest reasons why.
Ichthyosaurs are what happened when evolution took the blueprints for an orca, an eel, and a lizard and put them in the blender. Predatory marine reptiles that spanned nearly the entire Mesozoic, ichthyosaurs were incredibly diverse and successful, and may have been even older than we thought. A brand-new study reports large-bodied ichthyosaurs from only two million years after the end-Permian extinction, implying that ichthyosaurs likely evolved in the Permian and developed large sizes very quickly. Growing huge was far from their only talent, however. This video will focus on the mega ichthyosaurs that dominated the Triassic and early Jurassic, looking at their physical adaptations, ecology, and what we know about their lives. There’s also some juicy unpublished info I’ve gotten permission to share. For the sake of the video, I’ll define a “mega ichthyosaur” as any ichthyosaur that reached a maximum body mass of 15 tonnes or more. And for any documentary producers watching this: please highlight the Triassic more.

[@TheVividen]

Secure your privacy with Surfshark! Enter coupon code VIVDEN for an extra 4 months free at surfshark.deals/vividen

[@Mikailodon]

Just imagine, you’re alone, floating on the surface of the deep blue Panthalassa, and below your depth is the foreboding shadow of an Ichthyotitan, eating another smaller but still enormous ichthyotitan. I swear, it’s like Subnautica in real life.

[@chadgorosaurus4898]

People keep overusing the Mosasaurs when the giant Icthyosaurs are just as or even more terrifying than them.

[@dylans0630]

😨 unironic fear 😰

[@DreadEnder]

Like?

[@Paleowgh]

Oh GOD, STAAAHP

[@the_sprite_man]

Hi

[@flightlesslord2688]

The Great Dying: *happens* Icthyosauriformes: Oh no... anyway *becomes kaiju*

[@SlothOfTheSea]

My main takeaway from this video is that a blue-whale sized macropredator is utterly terrifying. Nature’s final boss. Great work as always. Ichthyosaurs are basically what we thought mosasaurs were as kids.

[@kingshark9057]

The big ones acted like sperm whales do the smaller ones are the scary ones they were pure hunters are acted like orcas do

[@francissemyon7971]

I had seen about the new surangular by PdLS. This is a new bone but still no teeth so far, because of this I'm still suspicious about toothed macropredation in ichthyosaurs above 20 m. Also, even with robust teeth, the snout reconstructions I see of S. popularis look really slender, I have a hard time seeing one ingesting a 20 t prey as suggested by Vividen. I'd also like to see more evidence of Himalayasaurus having such a robust skull, it seems to me the skull was hardly preserved. Isn't Thalattoarchon rather the most robustly skulled ichthyosaur ? I'm still very suspicious of this Temnodontosaurus bite force estimate from a non reviewed article, I have a hard time to believe it would bite harder than a large, more robust skulled Basilosaurus (20kN) or Kronosaurus with a 1.8 m skull (27 kN). Overall, for now I don’t see more firepower from those guys, even at 25 m×, than in what we see in the Livyatan skull and what we project from the Otodus megalodon dentitions.

[@AidanMartin]

or pliosaurs

[@bkjeong4302]

It’s quite unfortunate that the smaller, mesopredatory ichthyosaurs ended up being the iconic image and the view both the public and until recently academia applied to all ichthyosaurs. That would be like if Halisaurus or Phosphorosaurus was the default public image of mosasaurs.

[@frost7463]

I’m so glad my and Diocles’ work on Hector’s ichthyosaur could be featured in this. We don’t know how big it was, how old it was, or much of anything about it. But I will say, if the centra measurements are correct, it would easily be an animal over 100 metric tons. Beyond that, though, the size is very uncertain, and NO reconstruction should be taken as fact. I really hope that more remains can be found or the large centrum can be rediscovered for more information on what could be one of the largest animals that existed and would close the case on a mystery in paleontology that’s 150 years old.

[@TheVividen]

Your guys' work really is incredible, and part of that effort is establishing what we do and don't know. Hopefully more information comes to light soon!

[@archosaur_enjoyer824]

Hector's icthyosaur probably dwarfed the blue whale but guess we'll never know till we get an update :/

[@frost7463]

@@GoodrichthysEskdalensis It didn't get lost with the Matoaka. The Matoaka vanished in 1869. The giant centrum was discovered in 1877. Ergo, it is literally impossible that the centrum was on the Matoaka.

[@GoodrichthysEskdalensis]

​@@frost7463Oh yeah I didn't get to that part. I was just coming back here to delete the comment.

[@DreadEnder]

Amazing work! Awesome to see new material and work come to light! Also I agree about the reconstructions. I like what George E.P. Box said, “all models are wrong, but some are useful.”

[@radishinglad998]

While I'm always hyped to hear about potentially titanic fossils, I think there is something special about the largest animal ever existing happening to exist alongside us. That we can still go out and study it and that we can protect it from going extinct. That not everything huge and badass was in the past - we're living alongside monsters too.

[@arnigeir1597]

Well, we can never find all the fossils, nor does every species fossilise, so the blue whale being the largest animal confirmed is closely linked to it being the one we live alongside today.

[@TheVividen]

SOURCES Darius Nau calc on Ichthyotitan and Aust: www.deviantart.com/theropod1/art/Giant-ichthyosaurs-of-the-Upper-Triassic-961320408 Sperm whale suction feeding: www.nature.com/articles/srep28562#:~:text=Strong%20and%20sudden%20changes%20in,during%20post%2Dacquisition%20prey%20handling. Shonisaurus teeth: www.cell.com/current-biology/pdfExtended/S0960-9822(22)01761-4 Ichthyosaur integument: www.idunn.no/doi/pdf/10.1111/j.1502-3931.2001.tb00058.x Ichthyosaur speed: www.researchgate.net/publication/247855454_Swimming_speed_estimation_of_extinct_marine_reptiles_Energetic_approach_revisited Ichthyosaur blubber: www.sciencedirect.com/science/article/pii/S0012825222000496 Welsh Giant: www.app.pan.pl/archive/published/app60/app000622014.pdf Temnodontosaurus bite force: www.bbc.co.uk/programmes/articles/3gBPbbRKVJQxRMwYkkPqPGM/big-jaws-big-bite#:~:text=With%205000%20cm%C2%B3%20of%20muscle,a%20great%20white%20shark%20too. Cymbospondylus youngorum: faculty.umb.edu/liam.revell/pdfs/Sander_etal_2021.Science.pdf Shonisaurus group behavior: www.sciencedirect.com/science/article/pii/S0960982222017614 Shonisaurus coprolites: gsa.confex.com/gsa/2016AM/meetingapp.cgi/Paper/284943 Darius Nau Shastasaurus GDI: twitter.com/darius_nau/status/1781728382729801922 Swiss Tyrant description: www.tandfonline.com/doi/full/10.1080/02724634.2021.2046017 University of Bonn Ichthyotitan: www.uni-bonn.de/en/news/072-2024 Huene’s Giant www.cambridge.org/core/journals/geological-magazine/article/abs/palaontologie-und-phylogenie-der-nideren-tetrapoden-by-fried-rich-von-huene-pp-xii-716-with-690-text-figures-gustav-fischer-jena-1956-price-dm-88/40D12838DD3FA7557BDFE48CF8887DCD Ichthyotitan Histology: peerj.com/articles/17060/ Hector’s Ichthyosaur: paperspast.natlib.govt.nz/periodicals/TPRSNZ1873-6.2.4.1.52/1 End-Triassic Extinction onlinelibrary.wiley.com/doi/10.1002/9780470015902.a0001655.pub3 Upper Triassic paleobiota sjpp.springeropen.com/articles/10.1186/s13358-023-00269-3/figures/6 Ichthyosaur hydrodynamics royalsocietypublishing.org/doi/10.1098/rspb.2018.2786 Jiang et al. 2020 (Guizhouichthyosaurus macropredation) www.ncbi.nlm.nih.gov/pmc/articles/PMC7520894/

[@tyrannotherium7873]

It’s amazing that at one time ichthyosaurs were the top predators of the Triassic and Jurassic

[@frost7463]

They also held niches as apex predators in the early Cretaceous, they just weren’t as big as their nightmarish predecessors.

[@bkjeong4302]

@@frost7463 Chad Longirostria eating birds and sea turtles

[@frost7463]

@@bkjeong4302 ichthyosaurs kept becoming apex predators after mass extinctions, it's really funny. It happened in the triassic, jurassic, and cretaceous.

[@laseriedeladilophosaure9246]

​​@@frost7463et surtout les mosaur et les pliosaur avait déjà pris les places des super prédateurs des mer aux crétacé supérieure et inférieure

[@seanledden4397]

The lost fossil of Hector's Ichthyosaur reminds me of the legend of the Amphicoelius vertebrae!

[@TheVividen]

It's not for something that it's been referred to as Sea Amphi!

[@Kai0kenAssassin]

Ichthyosaurs are quite underrated in my opinion. These specimens are proof that there were other predators besides the more famous ones, like mosasaurs, that could rival them in size and power.

[@manzac112]

Rival? More like surpassing them at times.

[@jkjk7423]

Love this video, and I loved especially knowing more about Himalayasaurus! It's my favourite Ichthyosaur

[@TheVividen]

Thank you! I think it's my favorite too

[@user-rw4yi2xw5i]

​@@TheVividen I'm can tell you one my question:If biggest sauropods can outsized biggest whales,they should or would be likely Titanosaurs rather than other sauropods

[@laseriedeladilophosaure9246]

​@@user-rw4yi2xw5ioui je pense que soit c’est brachiosauridea ou un titanosauridé

[@user-rw4yi2xw5i]

@@laseriedeladilophosaure9246 you can write this on English?

[@TheVividen]

​@@user-rw4yi2xw5iIf they did, (which based on the reliable fossils we have in our possession does not currently seem likely), the titanosaurs would be the ones to do it

[@NomicFin]

Imagine being transported back in time to the Triassic in the middle of the ocean and seeing a huge ichthyosaur coming right at you...only for a far larger one to surface, grab it in its jaws, and drag it to the depths. There's always a bigger fish.

[@lightman3581]

Only less than 1% of the the life that has existed in the past has been fossilised and from that percent it’s likely that we might never discover more than 5% of these fossils. Makes me wonder what else might have existed in the past which we might never know about.

[@IndominusRex-wc1ey]

18:10 possibly the hardest line ive heard from a paleotuber in a god damn while

[@filipporaule4299]

i wonder if those colossal sized ichthyosaurs hunted even preys bigger then they are... possibly some giant filter feeding ichthyosaurs. knowing that relatives like hupesuchus are now considered to be filter feeders it might be possible that some shastasaurids would've evolved the same adaptations but scaled to huge sizes.

[@DreadEnder]

This was really fun to help you work on. Even if my contribution was just providing a couple seconds of footage.

[@TheVividen]

Thank you for helping out! It really helped ground the Aust section, I think

[@DreadEnder]

@@TheVividen whether it did or didn’t, I’m happy to help!

[@Paralititan]

The fact that we only now start to understand what the ecology of late triassic shastasaurs is, is wild as we know of them since over 100 years. I do have to say this regarding the smaller taxa Guizhouichthyosaurus and Besanosaurus: 1) the bromalite Guizhou-specimen reaks of an accidental ingestion to me, given the early state of digestion and the subsequent death. I think we need a few more specimens to say for certain if reptiles were on the diet. 2) I have seen the Besanosaurus holotype myself and can confirm that the internal content is fetal, so yes a pregnancy rather than diet. Lastly, the Rutland specimen is definitely not the best preserved specimen of T. trigonodon to date. Stuttgart has two complete specimens, both including a better preserved cranium and Hauff museum has a complete specimen as well. The Banz cranium remains the largest specimen for which a size estimate is plausible, but I have seen humeri and vertebrae which do tentatively suggest individuals that approximate that sperm whale size...

[@Velocir4ptor875]

imagine seeing ichthyotitan on ur local oceanarium💀

[@Caradhriastox]

yes about time! Im just sick of people saying that megalodon was the biggest sea predator of the past. I just love representatives from the dinosaurs age

[@YuasBirds]

Shastasairid icthyosaurs are really awe inspiring to think about, I honestly wish we still had some remnants of the icthyosaurs around so we could have a point of reference for these goliaths. Or just to have in general, marine reptiles come back!

[@DreadEnder]

It’s been quiet so I might be able to watch this today.

[@VanessaScrillions]

I loved your surfshark ad LOL. I am terrified of those ichthyosaurs stealing my identity

[@RexytheSeaBlimp]

The single most goated animal group of all time-THE SEA BLIMPS

[@DreadEnder]

These things are even more insane than I imagined!

[@postapocalypticwarlord4647]

Dragons? More like Kaiju!

[@fabianvidrio370]

Love your videos, pls do could megalodon survive the Triassic seas.

[@francissemyon7971]

I had seen about the new surangular by PdLS. This is a new bone but still no teeth so far, because of this I'm still suspicious about toothed macropredation in ichthyosaurs above 20 m. Also, even with robust teeth, the snout reconstructions I see of S. popularis look really slender, I have a hard time seeing one ingesting a 20 t prey as suggested by Vividen. I'd also like to see more evidence of Himalayasaurus having such a robust skull, it seems to me the skull was hardly preserved. Isn't Thalattoarchon rather the most robustly skulled ichthyosaur ? I'm still very suspicious of this Temnodontosaurus bite force estimate from a non reviewed article, I have a hard time to believe it would bite harder than a large, more robust skulled Basilosaurus (20kN) or Kronosaurus with a 1.8 m skull (27 kN). Overall, for now I don’t see more firepower from those guys, even at 25 m×, than in what we see in the Livyatan skull and what we project from the Otodus megalodon dentitions.

[@godzillakingofthemonsters5812]

Y'know Kinda interesting that the mosasaurs got big quick too Wonder what would've happened if maybe the asteroid missed Another video idea: real life Kaiju. Just the biggest of critters past or present.

[@reubenc0039]

Would love to see a video on mosasaurs sometime :) fantastic stuff! Thanks for all the hard work.

[@Otodusmegalodon]

This video was great..Also when something related to Yellowstone hyperpredator will be released??

[@widodoakrom3938]

Great job u make good works for science development

[@Crunchy166]

"It's time to dig up a kaiju!" Well said my friend!

[@frost7463]

Also, small correction: the giant centrum wasn’t sent aboard the Theresa Cosulich in 1876 as it was discovered in 1877 and described in 1878. It may have been sent later, though. Only time will tell.

[@TheVividen]

Good point!

[@dinodhanushyt]

Waiting for could theropods survive in the Cenozoic, part 3

[@TheVividen]

It's still on the dashboard!

[@minecraftdinokaijumdk992]

@@TheVividenWhat is the next location? (Ngl, I’m just as excited for the episode on Australia and South America as everyone else, though I also would want to know how the Asia episode would go. (Especially given the three biggest creatures ever of three different families lived there: Paraceratherium, Paleoloxodon, and Gigantopithecus.) Still, I’m excited for all of the episodes, regardless.)

[@user-ub5wf3tj1y]

Wonder how Zhuchengtyrannus would tackle the Paleo

[@TheVividen]

​@@minecraftdinokaijumdk992I'm not sure which continent I'll be covering next, but the next video I'm actively planning is one about Mesozoic diseases. Hopefully soon, regardless!

[@terhazza]

What's with the surangulars? Why don't we find other bones from ichthyosaur jaws or skulls? (Although IIRC Lomax speculated that Aust 'bone shafts' might be premaxilla).

[@darrylandtanyaspeed3577]

Lez goo more of the vividen

[@dinodhanushyt]

Waiting for Cenozoic theropods for Australia and South America

[@minecraftdinokaijumdk992]

Same, along with Cenozoic Theropods in Asia. (Mainly since that’s where the two largest land mammals to ever exist (Paraceratherium in the Oligocene, and Paleoloxodon in the Pliocene/Pleistocene) lived, so it would be interesting to see how both scenarios are tackled. Plus, it would be interesting to see how the smaller theropods would tackle Gigantopithecus, a.k.a. the largest primate to ever live. (Though something tells me that a King Kong joke would be likely. lol)) Also, as far as Australia goes, I wonder if the human fire-hunting technique would pose a serious problem even for them, or if they can manage it. Especially given that such an event, which also likely caused Australia’s Pleistocene fauna to go extinct, happened earlier there than in other continents outside of Africa. Also, for South America, I would be surprised if some theropods get outcompeted by the Biotic Interchange, but outside of that, I would imagine that South America would feel like home to them already outside of the giant mammals. (Think about it: Warm climate, predatory running birds, giant land crocs, and abundant food. If I was a theropod in Cenozoic South America, I would think it feels like home, also. Especially when the true theropods would be South America’s new apex predators . lol)

[@dinodhanushyt]

@@minecraftdinokaijumdk992 bet paleoloxodon will be a challenge for them

[@roadkillanonymous4807]

These things have got to be about the scariest critters nature ever concocted…that we know of…real life monsters

[@Damasen13]

Honestly, I wouldn't mind a Subnautica playthrough from you. (That random pic of Hemsworth threw me off lmao) Welcome back, Viv. BBC should definitely consider one of these giants in the new WWD.

[@TheVividen]

Recording this clip actually had me thinking about it haha

[@ANotSoPopularMan]

As I always say, Ichthyosauruses are mosasaurs running a dolphin software with a blue whale main frame.

[@SumMfGoober]

The reaper leviathan actually scared the hell out of me 😭🙏 Why you do deez to mee

[@TheVividen]

Everyone must pay the Reaper Leviathan tax

[@superiorcybergodzilla5670]

Surely there are some who survived

[@chingyik123]

real life large sized lizard dolphin

[@tamaltarudey8912]

Is it possible that Shastasaurus was a benthic feeder like the Gray Whale?

[@TheVividen]

Good question! While it's possible, Motani concluded that based on the eye structure of large ichthyosaurs it was unlikely that any of them were deep sea carnivores.

[@tamaltarudey8912]

Actually the Gray Whale is a coastal water Benthic feeder

[@TheVividen]

​@@tamaltarudey8912hmmm, then that might be possible! We don't have any indication that ichthyosaurs possessed jaw structures in any way comparable to baleen whales, however

[@kewb314]

Thank you for saying Nevada correctly

[@Takashikuubo]

I could imagine a drunk blue whale drowning his sorrows because he lost the title of the biggest animal to have ever lived on earth To a big lizard 😂😂

[@jessehutchings]

3:56 Bro I'm a dinosaur enjoyer not a PhD holder in aquatic dinosaur gynecology

[@skeptic9614]

I can’t access ur discord for some reason

[@user-ze3lk1ov5b]

Is the one they found in England

[@Siamotitan789]

Can you discuss the giant carcharodontosauridae from Thailand? PRC 61

[@TheVividen]

I haven't heard about it--which study was it published in?

[@Siamotitan789]

@@TheVividen I don't know, because information about Theropods is very difficult to find

[@Veterupristisaurus679]

It's 5 tons and 11 meters

[@Tyrant678]

​@@TheVividenBuffetaut and suteethorn 2012

[@TheVividen]

​@@Tyrant678I'll have to look into it!

[@32.duongvanhoangvu23]

This is Peak. Not related, but do you still keep the Google Doc files containing the estimate sizes of many T. rex specimens?

[@nfgrova6434]

oh so now you tell me that my 80 foot Liopleurodon wasn’t the largest marine creature in prehistory 😢 Edit: Yeah I know that WWD was exaggerating but it still hurts

[@maozilla9149]

nice

[@justaguyandadog2984]

4:25 im sorry mate, but i dont think a surfing shark will cut it against a shastasaurus

[@Phishacro]

permian icthyosaur 🗣

[@Intrusion498]

who the frick gave caseoh swimming lessons?

[@GeneralGoji]

Wouldn’t be shocked if we find a bigger one with spikes and atomic firepower

[@therumbleinthejunglee]

ichyotitan fans tap in

[@pedroroque829]

The ocean is still "glitched", my man forgetting about whales and especially the mighty largest animal of all time which can weight over 270 tonnes, the blue whale

[@G.I_Jane]

you'd think people who study these things could actually use more common sense with scaling these creatuers up but half the time you guys are circle jerking some estimate that is super off in 5 years time

[@rh_4m]

The people who are studying these ichthyosaurs are using the most common sense available. According to the information scientists have, these animals did get this big. I don't know what you would propose the alternative to be. And sure, there might be a lot of sensationalism around these creatures, and sure, their size estimates are a bit finnicky especially for the largest like ichthyotitan, but vividen is presenting the most up to date info. I don't know what kind of circle jerking you're even trying to describe here.

[@G.I_Jane]

@@rh_4m your average paleo community circle jerk, the same trends you bash in the early 2000s like giganotosaurus's sizing are the exact ones that occur now even with more 'accurate' methods. Its yap fest of going back to square one. Essentially meaningless and the other half of paleo fans are just closet scalies with bad deviantart accounts. Your community

[@oliyes406]

WELSH GIANT‼‼‼‼‼‼ YDDDWWWWWW🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿🏴󠁧󠁢󠁷󠁬󠁳󠁿💪

[@FroggeNacho4444]

Im gonna still say the hectors icthyosaur is a cannon marine reptile.