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Megalneusaurus, Before and After

Years earlier, I posted a picture of a Late Jurassic pliosaur known as Megalneusaurus. The illustration that I put up was based heavily on a skeletal drawing of Liopleurodon, it had hardly any detailing, and the skull was shockingly shrink-wrapped. Not my best work. You can see that post here.

I’m happy to say that I have recently done a revised drawing of this 25-foot long marine reptile, and I think that it’s a substantial improvement over the earlier illustration.

Below is the original drawing that I made of Megalneusaurus back in 2013.

And here is the “new and improved” version…

This drawing was made with No. 2 and No. 3 pencils on roll paper, with some touch-up tweaking on my computer. The animal, from the tip of its nose to the tip of its tail, measures fifteen inches long (1/20 scale). As for the fish, they’re just generic fish, I suppose. I tried to find images of fish fossils from the Sundance Sea, but I couldn’t find anything worthwhile.

Hope you enjoy it. Please like and comment.

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Requests for articles and artwork

A while back, I asked you, the reader, if you had any requests for articles and artwork that you would like me to do, but I received no reply. However, I recently looked at the search terms that come up on this blog’s administration page. Most of the terms concern subjects that I’ve already written about or illustrated, but there were a few others on subjects that I haven’t touched yet, or have only just alluded to. Terms which showed up frequently were (in order of frequency):

  • Alamosaurus (12)
  • Caenagnathus / Chirostenotes (9)
  • Pterosaurs (8)
  • Liopleurodon (7)
  • Mosasaurs (6)
  • Dakotaraptor (5)
  • Velociraptor (in color) (5)
  • Suchomimus (4)
  • Carnotaurus (3)
  • Oviraptor (3)

 

Others caught my interest as potential future art or writing projects, including:

  • Abelisaur
  • Allosaurus courting
  • Allosaurus head
  • Allosaurus walking
  • Australovenator
  • Deinonychus
  • Dinosaurs of Texas
  • Dracorex head
  • Elasmosaurus
  • Iguanodon head
  • Neovenator
  • Pachycephalosaurus keeping shelter
  • Styracosaurus
  • Triceratops eating
  • Tyrannosaurus juvenile
  • Lacrimal horns on dinosaurs
  • Mesozoic turtles
  • What dinosaurs lived on Long Island?

The last three sound like interesting research projects. Anyway, based upon what I have seen, I think that I can gauge what you would like me to do. So, I’m treating these statistics pretty much like a to-do schedule. Right now, I’m really hammering on a super-detailed drawing of a full-body T. rex, which I hope to have finished within one or two weeks, and then put up here for you to admire and comment on. After that, I’ll focus on the items on these two lists – the “frequency list” will take priority. I’m happy to say that some of these terms are on things that I’ve had in the back of my mind for a while, so this will give me the impetus to do them. Take care everybody, and keep your pencils sharp.

Ophthalmosaurus

Ophthalmosaurus

Ophthalmosaurus was a 20-foot ichthyosaur which lived during the late Jurassic Period in the oceans around Europe and North America. It is named after its distinct large eyes. The coloration in the illustration is based upon the Spotted Dolphin.

Megalneusaurus

Once again, I’ve noticed that a switch from paleontology to history-related material has resulted in my website views taking a nosedive. So, to appease the public, I am putting more prehistoric stuff on here.

Allow me to introduce Megalneusaurus. This creature was a large 25-foot marine reptile which lived in the Pacific Ocean along North America’s western coast as well in as the shallow Sundance Sea, which covered much of north-central North America, during the late Jurassic, approximately 155 MYA. It was a member of a group of animals called the pliosaurs, whose most famous members consisted of Kronosaurus and Liopleurodon.

So far, the only evidence that we have of this creature is what might be a single fragmentary skeleton discovered towards the end of the 19th Century consisting of some vertebrae, one flipper, a few ribs, and most of the pelvis. In 2007, scientists published a report in which they re-discovered the original locality where these bones were uncovered. Among the finds found were the stomach contents, consisting of the remains of belemnites – primitive squid-like creatures.

Megalneusaurus

Since a complete or even reasonably-complete specimen of Megalneusaurus has not been found, paleo-artists have a slight degree of elbow room in terms of how this animal looked in life. This drawing is heavily-based upon an old and inaccurate illustration of a Liopleurodon skeleton from the 1960s(http://plesiosauria.com/images/line_drawings/liopleurodon2_newman&tarlo.jpg). Firstly, Liopleurodon’s skull was actually a bit flatter than shown in that drawing. It also had more teeth in its jaws – the old illustration shows only the front teeth. Finally, and most obviously, it is depicted with a short somewhat triangular tail fin. I kept the head’s structure more or less as it was, put more teeth in the jaws, and made the tail fin diamond-shaped to make it more symmetrical. It’s unknown whether or not pliosaurs like Megalneusaurus actually had a tail fin, but I kept it here since it looked interesting. Besides, until a couple of years ago, no one would have guessed that mosasaurs like Prognathodon would have had shark-like tail fins, but there you go, that’s paleontology for you.

Check out the two websites below for more information on this creature:

News: Some prehistoric marine reptiles may have been dark in color

Hot off the presses! Scientists have an idea about what color Mesozoic marine reptiles, which are sometimes Romantically referred to as “sea dragons”, were in life. Apparently, some of them were dark or even black in color.

The findings were published in an article in the scientific journal Nature.  A group of paleontologists led by Prof. Johan Lindgren analyzed the well-preserved remains of an ichthyosaur from the early Jurassic (193 MYA), a late Cretaceous mosasaur (85 MYA) and a leatherback turtle from the Tertiary Period (55 MYA). Fossil skin and other soft tissues is extremely rare because they usually decompose before fossilization can take place. Fossils that are so well preserved that you can actually see pigmentation cells under a microscope are almost unheard of; only a handful of other examples have been uncovered within the past ten or so years.

The pigmentation cells in question here are called “melanosomes”. For those of you who have a vague knowledge of ancient Greek, you’ll know that anything that has “mela” in it means that it’s black – skin cancer is called menaloma due to the dark patches it forms, unusually dark colored animals are called menanistic, and other examples. So, melanosomes are pigmentation cells that are black or very very dark in coloration.

For a marine reptile, being black all over would be a big benefit. It is commonly taught in elementary schools that black absorbs heat. Reptiles are cold-blooded, and staying warm is a constant concern, especially when they spend a considerable portion of their time in the water. As examples, the modern-day American Alligator and the Marine Iguana of the Galapagos Islands are both colored very dark. Being colored black would help them absorb heat more quickly than if they were colored light. Even most whales and dolphins, which are technically warm-blooded, are colored black in order to absorb heat, due to the often frigid conditions of the water that they dwell in.

The modern-day Leatherback Turtle is black on top, whith a little bit of white speckling and stripes along the top of its shell ridges. Therefore, it isn’t surprising that its early Cenozoic ancestor would be dark-colored as well.

Mosasaurs were enormous aquatic lizards which could reach over 50 feet long. Their closest surviving relatives are monitor lizards, like the Komodo Dragon. This isn’t the first time that mosasaurs have been in the news. Not so long ago, it was revealed that they may have suffered from “the bends”.

Lindgren and his colleagues propose that the ichthyosaur may have been colored completely dark all over, rather than being dark on top and light on the bottom (this is called “counter-shading”).

Note: This does NOT mean that ALL ichtyosaurs and mosasaurs were colored in this fashion. It merely means that membes of these particular species were colored this way.

Well, the new year certainly has gone off with a bang. I can’t wait to see what the other eleven and a half months will bring.