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About Other / Hobbyist Fabio Alejandro22/Male/El Salvador Groups :iconspeculativeevolution: SpeculativeEvolution
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Lovecraft creatures: half man, half beasts by Dragonthunders Lovecraft creatures: half man, half beasts :icondragonthunders:Dragonthunders 61 8 Stegosaurus by Dragonthunders Stegosaurus :icondragonthunders:Dragonthunders 93 12 Triceratops horridus by Dragonthunders Triceratops horridus :icondragonthunders:Dragonthunders 89 20 Cambrian mars: Thyreocephala evolution by Dragonthunders Cambrian mars: Thyreocephala evolution :icondragonthunders:Dragonthunders 90 19 Imaginary titans by Dragonthunders Imaginary titans :icondragonthunders:Dragonthunders 139 57 Quetzalcoatlus by Dragonthunders Quetzalcoatlus :icondragonthunders:Dragonthunders 72 13 Anbonacetus, the swamp horror by Dragonthunders Anbonacetus, the swamp horror :icondragonthunders:Dragonthunders 80 13 Spinosaurus by Dragonthunders Spinosaurus :icondragonthunders:Dragonthunders 107 29 Regixornis (TMHOTW entry) by Dragonthunders Regixornis (TMHOTW entry) :icondragonthunders:Dragonthunders 62 10 Spawn of Cthulhu by Dragonthunders Spawn of Cthulhu :icondragonthunders:Dragonthunders 44 8 Pterosaur warrior by Dragonthunders Pterosaur warrior :icondragonthunders:Dragonthunders 48 10 Barosaurus by Dragonthunders Barosaurus :icondragonthunders:Dragonthunders 72 14 Tyrannosaurus rex by Dragonthunders Tyrannosaurus rex :icondragonthunders:Dragonthunders 87 19 Opisthosiren by Dragonthunders Opisthosiren :icondragonthunders:Dragonthunders 71 21 Emerocharia by Dragonthunders Emerocharia :icondragonthunders:Dragonthunders 85 28 Lepidovulture by Dragonthunders Lepidovulture :icondragonthunders:Dragonthunders 36 9


Tendaguripterus recki by Kana-hebi Tendaguripterus recki :iconkana-hebi:Kana-hebi 94 5 Likes Long Walks on the Beach by Sheather888 Likes Long Walks on the Beach :iconsheather888:Sheather888 44 8 Life and Death by Sheather888 Life and Death :iconsheather888:Sheather888 38 6 Carnohawk threat display by randomdinos Carnohawk threat display :iconrandomdinos:randomdinos 64 18 Poe - South Pole Animals by KingOvRats Poe - South Pole Animals :iconkingovrats:KingOvRats 40 21 Some doodles by Dontknowwhattodraw94 Some doodles :icondontknowwhattodraw94:Dontknowwhattodraw94 108 36 Springbuck by WillemSvdMerwe Springbuck :iconwillemsvdmerwe:WillemSvdMerwe 81 11 Scimitar oryx by Gredinia Scimitar oryx :icongredinia:Gredinia 23 0 Sundayfishsketch8 by Hyrotrioskjan Sundayfishsketch8 :iconhyrotrioskjan:Hyrotrioskjan 147 9 Colourful Sauropodomorph by Fireplume Colourful Sauropodomorph :iconfireplume:Fireplume 13 0 NAoC: Stegosnake by TerrificTyler20 NAoC: Stegosnake :iconterrifictyler20:TerrificTyler20 7 2 Kawaiiju sketches 2 by Spearhafoc Kawaiiju sketches 2 :iconspearhafoc:Spearhafoc 6 1 Bokrug by thomastapir Bokrug :iconthomastapir:thomastapir 34 2 Baryonyx walkeri by Kana-hebi Baryonyx walkeri :iconkana-hebi:Kana-hebi 141 19 Alien sea slug by hontor Alien sea slug :iconhontor:hontor 195 2 3. Fish from the paleozoic by PortentosaMan 3. Fish from the paleozoic :iconportentosaman:PortentosaMan 17 2



:iconspeculativeevolution: :icona-lost-world-project: :iconallocene:


Lovecraft creatures: half man, half beasts
It was a colossal and nameless blasphemy with glaring red eyes, and it held in bony claws a thing that had been a man, gnawing at the head as a child nibbles at a stick of candy. Its position was a kind of crouch, and as one looked one felt that at any moment it might drop its present prey and seek a juicier morsel. But damn it all, it wasn’t even the fiendish subject that made it such an immortal fountain-head of all panic—not that, nor the dog face with its pointed ears, bloodshot eyes, flat nose, and drooling lips. It wasn’t the scaly claws nor the mould-caked body nor the half-hooved feet—none of these, though any one of them might well have driven an excitable man to madness. 

H.P. Lovecraft, Pickman’s Model

Deep One
I think their predominant colour was a greyish-green, though they had white bellies. They were mostly shiny and slippery, but the ridges of their backs were scaly. Their forms vaguely suggested the anthropoid, while their heads were the heads of fish, with prodigious bulging eyes that never closed. At the sides of their necks were palpitating gills, and their long paws were webbed. They hopped irregularly, sometimes on two legs and sometimes on four. I was somehow glad that they had no more than four limbs. Their croaking, baying voices, clearly used for articulate speech, held all the dark shades of expression which their staring faces lacked.

H.P. Lovecraft, The Shadow over Innsmouth

I wanted to gather some other humanoids, but I only managed to find these two as the few that seem to exist physically in the universe of lovecraft, being the others found in dreamlands like the Nightgaunts.
Another dinosaur, one of the most iconic, and being one if not the largest known Stegosaur.

Something I have doubts exactly, where do the references come from that the biggest stegosaurus reached 9 meters? I was looking at some sources but they are popular books.
There is like a fragmentary adult specimen and its length was inferred from the scale of more complete specimens?

As well, I continue with the practice of textures to make the animal more convincing, so there is a bunch of scales, although I feel they should be smaller.

Based on Stegosaurus reconstruction by Scott Hartman
Triceratops horridus
Well, another dinosaur, one of the largest known Ceratopsid.

I'm also doing some practice with the textures to make the skin a little more convincing, I still need to practice a little more.

Well, I must say that I had nothing planned to publish at this point until I finished or have more or less something complete as teasers, however since it is the first anniversary of the publication of the SE giant size chart, I decided to make a mandatory update on how this going. First of all I must apologize for the lack of activity and almost the absence of progress in this last year, unfortunately and in these last months, I have had to quit in drawing and doing work due to problems of a family nature, which forced me to keep me busy to work in projects.
At the same time, I had planned to look if there were some new projects around the community to have more candidates, in addition to reviewing other potential projects that I didn’t add in the first place.

This being clarified, time for the updates.

Main size chart Update V2.0

There would be two important changes or updates in this, considering that most of the original work is more or less wonderful, the first and least obvious is the design change of some sketches that I did before, this due to certain aspects that I did not take into account how it can be aspect, proportions, coloration, among others. The second and more obvious would be to add new creatures of new projects as well as old ones which I had not noticed before or had been added in the last year.

Example1 by Dragonthunders
some of the new as an example


Alien size chart

Teaser2 by Dragonthunders

At the beginning of making this chart I thought that I was only going to have it separately in a file and I was going to mix the content of this one with the original one, however, due to the final size of the files, I should rule out the possibility of having a unique table, so it is about aliens, it will be completely apart.

On the project side it seems that I have managed to do well, I have found a considerable amount of them, not large since not all projects have described the sizes of their species or have not been completed, but enough to fill spaces, in this case and for being aliens I have run into a lot of giants that surpass even the blue whale or the largest of the sauropods.
Some projects that I have added so far are Snaiad, Nereus, ANU, Silvanus, Expedition, Horus and Dante and there are more in the making.


Real life size chart

I tried to take a different route in terms of work, making each individual species with more details, since I did not find the first table good, as well because I wanted to start practicing with paleoart, and have more experience with making animals (and because I like prehistoric animals like any other normal human being) but it will take a very long time to work.

At first I had also planned to put this table in conjunction with the original to compare both real and fictitious organisms, however, the greater the content, the less space was left for the real ones, so at the moment there is no way to add them alongside with the main SE size chart. However, I have had another use for these in this case with smaller comparison charts, which I had mentioned a long time ago, in which I can individually put related species both real and fictitious.


The others charts

The ideas I had in mind continue as planned, at this point I have prepared at least 2 tables for organisms larger than 100 meters, such as the Emperor sea strider, the Ebony blisterwing (jezz why Darwin have kaiju-like organisms) and some spec organisms that are still in progress.

I still plan on making a chart for organisms less than a meter, because sometimes the largest organisms of certain groups do not always tend to be titans the size of elephants, as well most aren’t visible enough in the main chart with the actual proportions.

And finally, A “Sapient size chart”, bringing together the most relevant sapient species of speculative evolution, I have already started it.

Sapien 1 by Dragonthunders
The first one :)

For other things, if someone has any questions, opinions or questions, you are free to ask.
However, I am not going to respond to suggestions on which projects I should add or not, in projects I will only hear the creators of these ones for anything.

Cambrian mars: Thyreocephala evolution

It's been about a year since I did an update of my project Cambrian mars, and in spite of it and despite continuing to make sketches with short information, I had not done something major updates, mostly because I had no interest in this and I wanted to focus my attention on other projects. However, these days I have felt a little encouragement to start working again, or rather to re-do this project since some of the ideas that I had previously made do not seem convincing for my actual understand, including the first idea that I had about the evolution of one of the main groups that I had created, the terrestrial anomalocarids or Thyreocephala, a group of Pananthropods that would be prominent in the Martian landscape as megafaunal organisms (main original idea here), being in a way convergent in aspect to vertebrates, although morphologically and anatomically they differ a lot.

At first my original idea for this group was to evolve like vertebrates, going through a stage of benthonic forms similar to early tetrapods that would colonize and adapt to life on land with the fins becoming limbs (link to the original concept), however, and now in retrospect, it seems a rather simplistic and lazy idea, considering the number of times that life would colonize land without pass for the same Tetrapod-like path, would be more plausible if these organisms took a slightly different route, a more arthropod like one. Also at the same time I wanted to preserve some of the original concepts, some created by my old friend Carlos or better known as :iconelectreel: here (look here), but making it properly plausible, and now I can say that I found a properly evolutionary path more or less plausible.

Even though I need to redesign some points of my timeline, major events, continental drift and probably some other concepts, for the moment I want to show the new redesign for the Thyreocephala evolutionary tree and diversity.


a) Early Anomalocarid (540 m.y.)
The first early forms that colonized a terraformed mars during the Cambrian, not so different from actual species.

b) Bethonic walker (470 m.y.)
After some millions of years of radiation, new anomalocarids groups started to colonize many benthonic niches around the coastal and shallow seas across the planet, being the Bethonic walker one of the early forms, redeveloping several pairs of legs under its body, in addition to modifying the arms into a comb-like shape to plow the seabed.

c) Tetradactilocaris (450 m.y.)
Some species of predatory habits over time changed the design of the arms, evolving into a limb-like “claw” composed of four appendages like fingers.

d) Flamboyant Brachiocara (430  m.y.)
The Flamboyant Brachiocara is perhaps the transitional key design in the evolution of the terrestrial dinocarids, since it has fully developed the limbs, being similar to some soft pananthropoda relatives in look, although with a strange characteristic, since internally it possesses a series of interlaced cartilaginous structures, almost similar as vertebrae, this being an adaptation to add a tough and flexible structure without the need for an external exoskeleton, in turn, each part of its body continues to change from their lifestyle as swimming creatures to being seafloor creatures, reducing several of their fins, changing the shape of their head, being more adapted to scratch and remove the silt, and its claws have changed, now being almost similar to some arthropod pincers.

e) "Decacarid" (390 m.y.)
This long-legged species had begun the transition to land, changing the morphology of the ancestral dinocarids even more, being now more compact, with more defined legs, some of the cartilage structures eventually merged, and now they are only articulated in two or 3 parts. The gills had changed and developed into book lungs, the body has begun not to depend on the exoskeleton to support itself, but on part of the cartilage endoskeleton under the legs that were connected at the base, becoming a kind of ribs.

Unlike the flamboyant, this form is mostly a coastal and fresh water dweller, being able to get out at low tide and even climb to high areas such as rocks or even trees.


Thyreocephala (380 m.y)

The only terrestrial Dinocarids descendants, they are the most prominent megafaunist groups on Mars in the next millions of years, their name refers to their armored head which is one of the few parts that still needs an exoskeleton, although in later species this changes and gradually the external part disappears.


f) Terrarchecara (370 m.y.)
Some of the first terrestrial species, they are mostly tree dwellers characterized by only using 3 of the 5 pairs of original limbs, the other two being used for purposes unrelated to locomotion. This still has part of the exoskeleton, however, it is almost vestigial and used for protection, its arms and part of the torso is now supported by "bones", however, being formed by cartilage.

The head has completely changed from its original shape, now with the remaining claws of the arms, converted into two pairs of mouthparts.


Arachnocorpua (350-230 m.y.)

The first prominent Thyreocephala group on land, these arachnid-like forms took the predatory and omnivorous niches for more than 60 million years thanks to their strong body armor which was used more for protection than body support, they were gradually replaced by their more graceful and unarmored cousins, being relegated to arboreal niches, their last lineages being gliding forms that became extinct during a major extinction event.


g) Deimucaracnids (350-290 m.y.)
The generic lineage of this clade, has some of the longest species, reaching more than 1.5 meters in length, are characterized by its 2 eyes on large eyestalk, its huge 4 pedipalps-like arms, 6 sturdy legs, and a very round and robust body divided in 2 segments. They were ferocious carnivores, capable of tearing down the 3 meters long amphibian “onychophorans”.


h) Hymenoscleria (330-230 m.y.)
These would be the first aerial forms to evolve in the Thyreocephala history, being creatures of completely arboreal habits, they were characterized by the development of long and rigid structures like wings in the hind legs, being long and that together with the body, it takes the shape of a round delta wing, which gave them the ability to glide long distances. This lifestyle probably saved them in the long term with the emergence of the flexible body Thyreocephala, although these gliders eventually became extinct with the loss of forested areas, being unable to survive an imminent mass extinction around 230 million years.


Chelitetrida (350 m.y.)

These are already a much more derived clade, being characterized by the loss of their exoskeleton and plates, most of the species of this clade is made up very small sized forms, although being at first inhabitants of the trees and forest ground, some would later give rise to new and larger forms in the following million years, and in turn this group will be able to survive in the long term.


Species example

i) Chromitodermus (340 m.y.)
This species of bright colors turns out to be a poisonous species, capable of producing biotoxins capable of killing any animal interested in digesting them.

j) Heretosquama (330 m.y.)
This species is one of the transitional forms to the first dominant groups of Thyreocephala, this for having lost the 2 pairs of atrophied legs that still possess primitive species of this group, at the same time of having developed eyelids that allows you to protect the eyes and presents a structure of the jaw quite unusual, which has a series of more elaborated muscles and ligaments connected between the bases of the mouthparts, being the precursors of the true jaws in posterior species.

They are inhabitants of semi-forested areas, being common in trees, however they are able to move on the ground.


Crassignatha (300 m.y,)

One of the first major megafauna’ herbivores and with the largest terrestrial species on land of its era, they were mainly formed by heavy herbivores with some minor omnivores, with robust and quite fat legs, compact and round bodies and long jaws with cheeks which mobilized and crushed the vegetable material around the jaw until entering the oral opening, and thus through large stomachs.


Species example

k) Lipothere (250 m.y.)
Lipotheres are the largest terrestrial species of its time, being large as an African elephant, bung weighting 4 tons, is a creature of small brain but voracious appetite, able to prune several trees and medium plants in a matter of hours, is able to feed on the variety of flora that grows in its territory thanks to its efficient jaw.


Asterodontia (270 m.y.)

First diverse group of they became a clade mainly formed by creatures that developed a fleshy jaw and formed by five mouthparts, two pairs being the original claws, and the last one that forms the upper jaw original part of the head.


l) Idipterans (270 m.y.)
These are the first Thyreocephala that developed true flight, this clade followed an almost convergent limb use with the gliders Hymenoscleria, using the hind legs as wing, however, instead of being formed by a rigid structure and only used to glide, in this lineage the wing is formed by a tissue membrane, which is sustained by three long phalanges, leaving a single finger free, while the 2 pairs of front limbs remain free. Its body has also adapted for such morphology, being the tail long and forming a small fluke, and the small head and with the upper jaw tipped, although the other four mouthparts doesn’t have the same shape, being in many species short and similar to beaks. Although this lineage has only species that reach a minimum of one meter in span, in the future it is likely that they will continue to grow, and perhaps at some point they will evolve into true titans.

m) Licaocaridids (270-220 m.y.)
They represent the largest and common predators of the first great age of the Asterodontians, being some species able to reach lengths of 3 meters, they became specialized hunters characterized by their robust jaw-shaped beaks, able to penetrate and cut the flesh of their victims , six agile and powerful legs with long claws in each one.

n) Corythorhynchid (270 m.y.)
Major herbivores with some omnivorous species, these are a very cosmopolitan medium to small sized animals, characterized by its rather structured digestive system able to better absorb nutrients, part of this excels in some species as a hump, and also by its strange ornaments derived from its upper jaw, varying in use and shape.

o) Hirsuticara (230 m.y)
Being early branch of the Corythorhynchids, Hirsuticarans are one of the best adapted Thyreocephala to cold climates, being able to maintain their temperature by themselves. Most are burrow dwellers, however, probably after first Asterodontia era, they are probably the possible heirs of a new world being able to survive the imminent mass extinction on Mars.

Imaginary titans

For some time I had an idea to make a series of draw comparison related to the idea of doing a “before and after” of certain prehistoric animal reconstructions, something similar to what users here on deviantart has done with draws or silhouettes, however, instead of being just one animal comparison, these would be properly chart showing the changes of such animals over the years, based on a specific topic or a specific documentary.

Here, I chose a particular topic to begin with, the case of the oversized animals, creatures that once were considered to be beings of massive length or mass by the paleontological community or in most of the cases, in the popular media, and have been changed over the years with new discoveries or re-interpretations, some of the estimations are quite light in changes which some can still be considered as giant creatures even with the slight reduction, others are really marked such measures changes to the point it seems like a joke that once was considered to be giants at the first place, and some are in the brink to change with a new discovery in any moment.

I must say that I have tried to collect only estimations made in the scientific field both popular (e.g., documentary) and professional, so there will not be estimations made in common entertainment media such as movies (Jurassic Park), fictional books (Kronos Rising) or video games (Ark)

If anyone has any complain or critic about the information, size, species or anything else, and even some suggestions for others oversized prehistoric animals, you’re welcome to tell, especially if I’m wrong, all for the sake of accuracy.

1) Pachycephalosaurus
It seems from many years since its discovery, this large Pachycephalosaur was considered to be 8 meters long, at least the original upright kangaroo posture interpretations which was common in many book illustrations, toys and old media that I guess was based on original ornithopod proportions looking that the head was smaller in comparison with the body. (If anybody knows a better reason you’re welcome to correct me)

Current estimates
In recent years there was a reinterpretation of the proportions of Pachycephalosaurus this based on several more complete specimens, giving it a change of look and also of size, now being a 5 meters long herbivore, still being the largest of its group.

2) Ornithocheirus (Tropeognathus)
This very fragmentary genus of pterosaur first discovered in UK, was featured in the documentary walking with dinosaurs as a flying giant of around 12 meters in wingspan and weighting 100 kg, being one of the largest pterosaurs ever. 

Current estimates
To explain a little why I added two pterosaurs, the actual Ornithocheirus (a) which had a very problematic taxonomic history with many fragmentary remains classified to this genus, with around 28 species in total named, but at the end many of these were considered to belong to separate genus, some from the same family and some others from different affinity, with only now one type species, O. simus, being this one around 5 meters of wingspan, and never being 12 meters.

The actual pterosaur which the WWD refer as “Ornithocheirus mesembrinus” was actually Tropeognathus mesembrinus (b) from Santana formation, but this wasn’t estimated to be 12 meters in any point either, the largest specimens so far know in that time were about 6 meters, and the specimens which the documentary were suppose to be base on (MN 6594-1 specimen), is estimated to be about 8 meters of wingspan, being not a giant, but still a pretty large pterosaur.


3) Amphicoelias fragillimus
This species was described in 1878 by Edward Drinker Cope, Being the holotype specimen a vertebra of 1.5 meters in length (AMNH 5777) and a femur, this get lost in some point to never to appear again for unknown reasons (probably due to poor care that destroyed the holotype) and only leaving as a record the existence of these notes and sketches.  Throughout the years, based on what has been left, attempts were made to make possible estimates of the size of this specimen, the majority being inferred that this species has the same proportions of more complete specimens of Diplodocids, giving a size estimation of 58 meters in length, with a weight of 120 tons, making it one of the largest dinosaurs that ever existed.

Current estimates
There have been debates about the possible length of the specimen AMNH 5777 over the years, this mostly because the only thing left of the original are only notes which It has been suggested that could contain typographical errors in the measurements or even be completely wrong, and taking proportions of smaller species not always turn out to be accurate or even plausible, so make an length estimation of this species based on the original vertebra turns out to be a complicate challenge. Of course as the chart is about originally oversized animals and then were downsized, I had to see if someone had tried to make an Amphicoelias smaller version with a plausible interpretation to be part of this chart, good thing there is one.

In this case I used the Amphicoelias reconstruction by :iconspinoinwonderland: , being 48 meters long.


4) Leedsichthys problematicus
The great Jurassic filter feeder ray-finned fish pachycormid discovered in the Oxford Clay Formation, was subject to many size changes, over the years it was difficult to give an accurate or plausible size estimation because of the poor remains found, at first estimated to have a measure of about 9 meters in proportion to the Hypsocormus genus , but around the 80 the discovery of a new pachycormid, this called Asthenocormus, led to new interpretations of the possible length from 13 meters to 27 meters, based on an extrapolation of the gill basket size, in some cases in popular scientific media mentioned to even be around the 30 to 35 meters long.

Current estimates
Some years after the discovery of many new specimens, like “Ariston” (PETMG F174), Dr. Jeff Liston in his studies estimated that Leedsichthys was smaller than what was thought, being about 9 to 10 meters in first estimations, and in later specimen comparison it give lengths between 7 and 12 meters, also pointing out that linear extrapolation of the gill basket would be flawed because gills grow disproportionally in size for the oxygen demand of a huge body. The most plausible estimations now are around the 16 meters.


5) Kaprosuchus
The unusual “boar croc” was discovered and described in 2009 by Paul Sereno and Hans Larsson in the monograph "Cretaceous Crocodyliforms from the Sahara" together with other specimens of Saharan Crocodyliformes. Being the holotype a well preserved skull (MNN IGU12) of about 50 cm, Sereno give an estimated length of around 6 meters.

Current estimates
As far I can found, there aren’t any background affirmation for the original Sereno estimations, even more there are been some counterarguments for such size estimations based on comparisons of actual crocodilians with a same head size, as well with more complete relatives like Mahajangasuchus, the most plausible estimations for the actual holotype put the length of Kaprosuchus in 3.3 meters.


6) Quetzalcoatlus
After the first fossils were discovery in the Javelina formation at Big Bend National park, Texas, it was estimated 3 probable wingspan size extrapolated from the proportions of others pterosaurs, being 11, 15 and 21 meters, being the middle one choose, but very light in weight being estimated to be less than 100 kg.

Current estimates
After subsequent discoveries of small specimens of Azhdarchid and a better known of the morphology of these ones, there were quite a few changes in their proportions, resulting in a more compact animal than previously believed; now it is estimated to have an 11 meters wingspan.


7) Allosaurus maximus (or Saurophaganax maximus depending on how valid still it is)
This Allosaurid named by Daniel Chure in the middle 90s, has gone through an interesting history of genus validation based on several specimens since the early 30s for what belongs to it, and even now the legitimacy of this genus is in dispute and with consideration of most of the specimens belong to Allosaurus (As well Epanterias).

Something remarkable about this theropod has been the estimates of its length, which would make this Jurassic theropod the largest of all from that period, being at the same level as the Cretaceous theropods in size, with a length of 14 meters in length.

Current estimates
It seems that there is no evidence supporting such lengths as the original estimates is considered to being incorrect, the specimen which belongs is probably an 11 meters long animal. Based on Allosaurus reconstruction by :iconscotthartman:

8) Spinosaurus
The enigmatic African spiny theropod, for many years this Spinosaurid had been one of several contenders to the title of the largest theropods in history thanks to several estimates made over the years, being first at least 15 meters long and with a weight of 6 tons, but by the end of the 20th century and in the beginning of the 21st century this creature get its highest estimations, being the largest based on Suchomimus body proportions in relation on their skull lengths, making it a great theropod of about 18 meters long and a weight of 7 to 9 tons, although some posterior mass estimations give it a body mass of about 11.7 to 16.7 tons. Spinosaurus in this form became a very iconic image for many years in popular culture.

Current estimates
Over the years there were quite a few counterarguments about the methodology used to make a reasonable approximation of the length of Spinosaurus, even some making new size estimations giving to this theropod a body length between 12 to 14 meters and a body mass of 12 to 20 tons, although these were criticized too for the theropod choices.

In 2014 things took an unexpected turn with the announcement of a new specimen, the FSAC_KK 11888, a partial subadult skeleton from Kem Kem beds, North Africa, which presented quite different proportions from what was estimated or speculated, showing Spinosaurus as short legged theropod of semi-aquatic habits, However, in the following years the veracity and validation of the specimen as Spinosaurus has been doubted, althouth being asserted in several cases, but not described properly and in full format.

From these proportions, it is believed that some of the largest specimens could have reached 15 meters in length as was estimated early, and not being the tall creature as the Suchomimus original proportions suggested.


9) Rhamphosuchus
This great Miocene Tomistominae (False Gharial) from India, only know by fragmentary tip jaw remains, was once considered to be one of the largest crocodiles ever, with a size estimation of about 15 to 18 meters for many decades.

Current estimates
After a re-study in 2001, it was downsized to a length of about 8 to 11 meters.

10) Bruhathkayosaurus
This supposed sauropod titanosaur was discovered in the region of Tamil Nadu, in the district of Tiruchirappalli, around 1989, being the remains a part of the pelvis and the tibia, these were referred to as belonging to a theropod by the shape of the Ilium, however, a later opinions determined it as a sauropod, probably a titanosaur around 1999. The measurements given at that time put it as a gigantic animal of around 35 to 40 meters in length, with an estimated weight of 175 to 220 tons, turning it into the heaviest terrestrial animal ever to have existed, aside of Amphicoelias.

Current estimates
Did you ever hear the tragedy of Bruhathkayosaurus the giant?
Seriously speaking, the history of the discovery of this "sauropod" could be said to be a tragedy since the only known remains discovered by Yadagiri and Ayyasami (those who were behind the discovery and identification of the supposed "stegosaurus" Dravidosaurus which is recognized now as a plesiosaur) were not properly recorded or conserved, these were described poorly, they took terrible pictures of such specimens, they made quite terrible sketches and to make it worse after the discovery they did not bother to collect those remains and the most terrible thing, they left them at the mercy of the Indian monsoons and erosion for the next 15 years after the discovery.

So there are 2 ways to see this in a speculative way given the situation: Option a, in the case that this genus has been what was suggested, a sauropod, the size of this would not have been the one that had been suggested years after its discovery, if an estimate can be made based on the measurements given of the remains, the length that could be obtained would be much less than the proposed 39 meters, being something approximately an animal of 28 meters in length or less, and probably with a much lower weight than previously estimated, probably being with a mass close or less than for example, Giraffatitan.

Or Option b, is just a 2 meter long tree trunk remain and a bunch of rocks with the shape of an eroded Ilium.

So pick one.


11) Kelmayisaurus
This theropod carcharodontosaurid from the early cretaceous was discovered in the early 70s in the city of Karamay, Xinjiang, western china, is known from a very fragmentary holotype formed by a complete left dentary and a partial maxilla. The main peculiarity of this theropod came from another specimen mentioned in the book “The Dinosaur Project: The Story of the Greatest Dinosaur Expedition Ever Mounted”, being the species called “K. giganteus”, being referred from a fragmentary giant vertebra column, it was estimated to had a length of about 22 meters, making it one of the largest theropods known.

Current estimates
The mentioned “K. giganteus” is considered to be a nomen nudum and the actual vertebrae column remains probably belongs to a sauropod. The original holotype specimen was estimated to be 9 to 11 meters of length making it a medium size carcharodontosaurid.


12) Mosasaurus hoffmanii
At first I wanted to introduce estimations made to the Tylososaurus made by "WWD: Sea Monsters" because was emphasized that these reached a length of 18 meters in length, being quite exaggerated with the current estimates that said that they reached 14 meters at maximum, however, I saw that it was more appropriate to introduce a much more recent size estimation mentioned in a scientific article, in this case of the specimen  CCMGE 10/2469 discovered in Penza, Russia, being estimated to have a size of about 17 meters long based in a head-body radio of 1:10 by Russell (1967), making it the largest Mosasaur ever.

Current estimates
Giving the point that for such proportions make people draw Mosasaurus with Tylosaur bodies, one person (mention below) took the time to do their research, and as a result, his detailed research revealed that Mosasaurus was quite robust and bulkier in comparison to its relative, giving it a different body ratio and making the 1:10 body-head radio inaccurate. The current estimates make the Penza specimen around 12 to 13 meters in length.

Based on M. hoffmanii reconstruction by :iconpwnz3r-dragon: 


13) Megalosaurus
It would seem strange to put a very outdated reconstruction in this place, however, at the time it had been considered as real by early paleontology. So, Megalosaurus could earn the title of not only being one of the first dinosaurs identified, but also for being the first oversized dinosaur ever, in their first reconstructions created by William Buckland considering him as a massive quadruped lizard with an upright posture of amphibious habits, based in estimations given by Cuvier, this was calculated to be a 12 meters long creature with a weight of an 7 ft tall elephant.

Current estimates
After the lizard model was abandoned, the original size estimations were considered to be quite exaggerated with new reconstructions, so most of the later estimations calculated Megalosaurus to be about 9 meters in the beginning and being in recently decades calculated to be 6, 7 or 8 meters long, with a weight less than a ton.  
Based on Megalosaurus skeletal reconstruction :iconscotthartman:

14) Iguanodon
Like with Megalosaurus, at first Iguanodon was estimated to be a massive lizard like animal being extrapolated the proportions at first from an iguana because the resembles of the Iguanodon teeth with these ones, giving a size estimations of about 18 meters long. 

Current estimates
Again, like Megalosaurus, the lizard model disappeared and over the time this animals has gone through several alterations in their body shape interpretations, varying in designs over the years until they reach their final form (?) being a semi-quadruped herbivore with disproportionately huge hands, with a length around 10 meters and a weight of 3.4 tons, with inferred specimens that can reach 13 meters long.
Based on Iguanodon skeletal reconstruction by :iconscotthartman:

15) Megalodon
Formally Carcharocles megalodon, It has been a shark with problematic size estimations thanks to its many fragmentary fossils being thousands of teeth and some vertebrae, which has given several measures, from the original 30 meters long Bashford Dean estimation in 1909 based on a jaw reconstruction, being downsized to 13 meters to a time later being estimated with a size of 24 to 25 meters long as maximum length.

Current estimates
Actual estimations give a length of about 16 meters to a maximum of 18 meters.

16) Liopleurodon
The biggest size estimation given to a pliosaur ever, the genus Liopleurodon had been described as a giant 25 meters long and weighing around 150 tons in the WWD series being based to fragmentary fossil teeth remain, it becomes one of the documentary's most iconic animal as well one of the most iconic pliosaurs next to with Pliosaurus or Kronosaurus.

Current estimates
The history of the Liopleurodon oversize case is already one the most known around the paleontological community both amateur and professional, that has caused wars of discussions and lots of defenders as well as opposites, and at the end letting a legacy and the perpetual idea of super pliosaurs, but as far is know, there hasn’t been any super pliosaurs and less super Liopleurodon discovered so far, although there has been wild estimations of 15 meters long specimens of others species, which at the end these became very dubious for how fragmentary the evidence has been.

The estimations made by the documentary were not in some points supported by some scientific article or any authority in the matter like with "Ornithocheirus", just made to get the attention of the public, as well, such measure was doubted even for being a maximum size, and most of the estimations made after based on the original remains in comparisons with others Pliosaur suggested that the actual Liopleurodon was 10 meters long, at least at first, and from here Liopleurodon gets smaller and smaller. Studies of other specimens such as Kronosaurus and the discovery of a complete specimen of L. ferox which shown that the skull was 1/5 of the body size gave an approximate length of 6.9 meters, based on the largest specimen found.

Minor text changes.
Liopleurodon fin proportions changed.

Another giant, one of the largest flying animals ever with 11 meters.

Edit: change in arms proportions and fingers.
Anbonacetus, the swamp horror
Anbonacetus is a fierce and quite stealthy aquatic predator of about 5 to 6 meters long, being a resident of the extended swamps and mangroves of a warm and insolated Europe, in an alternative timeline where the continent has been isolated from the rest, being an indefinite continuation of the Eocene. It is one of few descendants of the archaeocetes that adapted to the life of freshwater and coastal environments, taking a very slowly lifestyle, with a low metabolism, living under the murky waters between the large islands of vegetation, is an ambush hunter that prey on diferent medium size animals.

It's lifestyle has led to a quite aberrant appearance, with a robust jaw of which there are very prominent, long teeth without lips, quite tiny eyes located above the head, a very robust body, front legs with long claws that use to remove mud or vegetable matter.


This concept was supposed to be something longer for an entry of a competition on monsters, however I could not finish it on time, so here is at least the idea about it.
Well, with this is the second time I do a Spinosaurus, the first one was following the the quadrupedal form around 2014, guess I was wrong to just jump for sensational news and make stuffs based on it.

Based on Spinosaurus aegyptiacus by Franoys
So, this would be a stupid question but, there is any good or at least decent skeletal reconstruction of Bruhathkayosaurus an Amphicoelias? 

I know that the first is almost nothing but sketches of its remains and the second is just one vertebra, however, I wondered if anyone ever created a reconstruction that more or less tried to approach how the animal could have been without using the exaggerated estimates given in each case. Is something I need to know for an uncoming work I'm doing.


Fabio Alejandro
Artist | Hobbyist | Other
El Salvador



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Sporedude135 Featured By Owner Nov 19, 2017
I really love your future animal creations! Keep it up! You’ve inspired me to try my own version of the future, but with my fictional Continent simply known as “The Continent,” thrown in there. I will link the creature I make (probably use Spore for this because I can’t draw worth of anything) when I’m done. I hope you will like it!
AddieMins Featured By Owner Nov 16, 2017  Hobbyist Digital Artist
I don't really understand this "All todays" thing, but it is interesting nonetheless.
Velociraptor-King Featured By Owner Nov 13, 2017  Hobbyist Traditional Artist
Thanks again!
Dragonthunders Featured By Owner Nov 13, 2017  Hobbyist Artist
You're welcome :)
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