Genus: Kaprosuchus

…an extinct genus of mahajangasuchid corcodyliform that lived during the Upper Cretaceous period. Kaprosuchus was largely thought to be a terrestrial predator due to the positioning of its orbits, which are positioned dorsally, and its enlarged caniniform teeth are sharp-edged and straight. Kaprosuchus likely was an ambush hunter and hunted like a big cat, using its large tusks to take down relatively large dinosaurs.



Images: Jeslin and Carol Abraczinskas


Loricata in the AMNH.
Rausuchids, crocodylomorphs, phytosaurs amd crocodylians.
Photos by me

Loricata en el AMNH.
Rauisuquios, crocodilomorfos, fitosaurios y cocodrilos.
Fotos mías.


A study of Saurian morphology: Pseudosuchia (part 3)

Both Armadillosuchus (armadillo-croc) and Simosuchus (pug-nosed croc), and their other conveniently named relatives such as “duck croc” and “cat frog” belong to the suborder Notosuchia, a diverse group of terrestrial crocodylomorphs. They are identifiable by their relatively short skull, small body size, and erect limbs. The variation of teeth shape between genera suggests that the group evolved various feeding behavior, including the likely-herbivorous Chimaerasuchus.

Gavialis, commonly known as gharial, is an extant member of the order Crocodilia which consists of three families, Crocodylidae (true crocodiles), Alligatoridae (alligators and caimans), and Gavialidae (gharial and false gharial). It is distinguishable by its elongated jaw, optimized to complement its piscivorous diet. 

And thus this post nicely concludes Pseudosuchia, which coincidentally finishes nearly at the same time as my Kaprosuchus-inspired Charizard. Thanks to everyone who suggested anatomy inspirations. It should be ready to publish tomorrow. Next week’s theme will be Pantestudines, specifically Testudinata (which is nice because I’m trying to finish Blastoise).

I’ve also made my daily drawings available as T-shirts as demanded by some. It will take me a while to process all the files, so expect me to add 3 drawings per 3 days like I do here. Links below.

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Daily Drawings T-shirt · Other Products · Find me elsewhere

Anatosuchus minor, a terrestrial notosuchian crocodylomorph from the Early Cretaceous of the Republic of Niger, living about 112 million years ago. A fairly small animal, it was only about 70cm long (~2'4"), with an unusually broad duck-like snout – giving it a superficial resemblance to the fictional “crocoduck”. It also had a highly sensitive long nose, which probably allowed it to root around in vegetation for small prey, and sharp hook-shaped teeth to snag fish and frogs from shallow water.

Unlike modern sprawling crocodilians, many ancient croc-line archosaurs were active upright walkers with a diverse range of forms, filling many different niches alongside their more famous dinosaurian cousins.

Sotmatosuchis inermis

…was a very large (10m/32ft) stomatosuchid crocodilian from the late Cretaceous of Egypt. Unlike many other crocodyliforms it is largely unknown what exactly S. inermis ate. Its flattened skull had a long, lid-like snout which was filled with small conical teeth. Some theorize that the mandible might of been toothless and supported a pelican-like throat pouch. 

Sadly the only known specimen (a large skull, collected by German paleontologist Ernst Stromer) was destroyed when the Munich Museum was bombed in 1944.


Animalia-Chordata-Reptilia-Crocodylomorpha-Neosuchia-Stomatosuchidae-Sotmatosuchis-S. inermis

Image: Dmitry Bogdanov

Marine Reptile Month #9 – Metriorhynchus

Middle-Late Jurassic period (167-155 mya)

The “sea crocodiles”, or thalattosuchians, were crocodyllians highly adapted to marine life – and the metriorhynchids took this to the extreme. They completely lost their osteoderm “armor” to become more streamlined, developed paddle-like limbs, and even had shark-like vertical tail fluke.

How Metriorhynchus and its kin reproduced is still unknown, as no fossil eggs or embryos have ever been found. Their fully-aquatic anatomy makes it seem unlikely that they were capable of hauling out onto land to breed, so it’s possible they evolved the ability to give birth to live young, much like several other lineages of marine reptiles. However, no other archosaurs are known to have ever developed viviparity, so if these animals were capable of it they would be unique amongst the entire group.

Color palette used: “Galactica

Pietraroiasuchus ormezzanoi from the Lower Albian of Pietraroia Plattenkalk (specimen PC-1). B, illustration of the skeleton based on photographs of the specimen and drawn using Adobe Illustrator. Fractures have been filled in grey. Fracture 1 is original; fracture 2 is a broken area that fits perfectly in the specimen, so the centrum on both sides of the fracture is the same element. Scale bar = 150 mm. Ant, anterior; post, posterior. The cartilaginous sternal ribs are depicted in light grey. Thoracic vertebrae 1–10.

Skull of Pietraroiasuchus ormezzanoi (Lower Albian of Pietraroia, Italy) specimen PC-1 exposed in ventral aspect. A, photograph. B, illustration of the skull based on photographs of the specimen and drawn using Adobe Illustrator. Bottom left, magnified cervical centrum in posterior view. Early eusuchia 

Early eusuchia crocodylomorpha from the vertebrate-rich Plattenkalk of Pietraroia (Lower Albian, southern Apennines, Italy). ANGELA D. BUSCALIONI, PAOLO PIRAS, ROMAIN VULLO, MARCO SIGNORE, CARMELA BARBERA. Zoological Journal of the Linnean Society. Volume 163, Issue Supplement s1, pages S199–S227, December 2011


A study of Saurian morphology: Pseudosuchia (part 2)

Reposting because I have no idea what happened but my post disappeared? Now that I’m fully sober I should add some information about these fellas.

The three depicted above belong to the group Crocodylomorpha, a group that was very diverse during the Mesozoic. Sphenosuchus was a small, gracile basal crocodylomorph that might have been biped for a short burst of time—just like today’s Basilisk lizard for example.

The other two represent a major clade of marine crocodiles known as Thalattosuchia, Neptunidraco is classified under Metriorhynchidae, a family of fully aquatic crocs which had lost their scutes and developed flipper-like limbs and tail fin to complement their pelagic lifestyle. 

Machimosaurus on the other hand, represents the Metriorhynchidae’s closest relative Teleosauridae, a family of gharial-like marine crocodyliforms. This fish-eating genus recently circulated around the internet after the announcement of M. rex, probably the largest teleosaurid known at (est) 9.6 m (31 ft) long—but we all know it’s mostly due to the “rex” on its name.

I should probably start writing proper captions for my future posts because the world needs to learn about flippercroc and its funky relatives. They’re like, the weirdest crocs ever. Or not. You’ll find out in 3 days.

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Will Art for Science · Find me elsewhere

For the love of crocodylomorphs

by Darren Naish

Crocodiles, alligators and gharials are the modern members of a far grander, far more diverse clade of archosaurian reptiles termed Crocodylomorpha. It’s gradually becoming better known that, in additional to including amphibious, long-skulled taxa like the living ones, the group encompasses an incredible array of terrestrial and semi-terrestrial omnivores, herbivores, carnivores and insectivores.

(Read more → Tetrapod Zoology)

(Buy merch featuring the above image! → Darren Naish’s Redbubble shop)


Once you Poposaurus, You Can’t Stoposaurus!


Poposaurus is one of those prehistoric reptiles that no one is exactly sure how to classify, and it has been shifted around to a few different groups. It seems like the general consensus now is that this bipedal archosaur is most likely a Rauisuchian, along with awesome creatures like Postosuchus and Polonosuchus.

Unlike most other prehistoric archosaurs (a big ass possibly polyphyletic group of reptiles that includes crocodylomorpha), this creature was bipedal. There were a few other bipedal early archosaurs (here’s a good article by Brian Switek).

They’re known from fossils found throughout the American West, and they were up to 4 m long. As you might assume to look at them, they were swift predators, probably capable of taking down larger and fast moving prey.

Find out more about their relatives here:

illustrations by Smokeybjb and Jeff Martz/National Park Service