Suchomimus

*Suchomimus tenerensis*

* Timothy Bradley Artwork
* Robert F Walters Artwork

***Suchomimus*** (Greek for "crocodile mimic") is a genus of large spinosaurid that lived 112 million years ago, during the late Aptian stage of the Cretaceous Period in Niger, Africa. Sharing traits with its more larger, relative **Spinosaurus aegyptiacus**, *Suchomimus* was one of the dominant theropods of its time and environment.

Unlike most large theropods, *Suchomimus* had a very long, low snout and narrow jaws studded with some 100 or more teeth; similar to structure of Fishing Hooks. The tip of the snout was enlarged and carried a "rosette" of longer and sharper teeth.

The animal's head and mouth anatomy is reminiscent of slim snouted crocodilians, such as the Australian fresh water crocodile, African slender snouted crocodile, American crocodile, Orinoco crocodile, and both gharial & false gharial, types of large crocodiles with a very long, slim snout, from the regions of Asia, Oceania and south america, that they presumed to have similar habitat and ecological niche. Although it is well known that the spinosaurids had rather piscivorous behavior.

*Suchomimus* also had a medium sized extension of its dorsal vertebrae which may have held up some kind of low ridge or sail of skin, as seen in much more splendid form in *Spinosaurus*. Detailed study shows that the holotype of *Suchomimus* was about 10.9-12 meters in length and weighing between 3-5 tonnes. Sereno stated that Suchomimus could've grown larger by some feet than the holotype. In fact the description paper of Suchomimus never mentioned that the holotype was immature.

The overall impression is of a big and gracile creature that ate large fish as well as all other sorts of meat (pterosaurs to small sized dinosaurs when available) more than 100 million years ago, when the Sahara was a lush, swampy habitat full of life unlike the barren desert of today.

## Discovery and naming

[1]In the year 1997 American palaeontologist Paul Sereno and his team, at Gadoufaoua discovered Fossils that represented about two-thirds of a large theropod dinosaur skeleton in Niger. The first find, was a giant giant thumb claw, was made on 4 December 1997 by David Varricchio. In 1998, Sereno, Allison Beck, Didier Dutheil, Boubacar Gado, Hans Larsson, Gabrielle Lyon, Jonathan Marcot, Oliver Rauhut, Rudyard Sadleir, Christian Sidor, David Varricchio, Gregory Wilson and Jeffrey Wilson named and described the type species *Suchomimus tenerensis*. The generic name *Suchomimus* ("crocodile mimic") is derived from the Ancient Greek σοῦχος, *souchos*, the Greek name for the Egyptian crocodile god Sobek, and μῖμος, *mimos*, "mimic", after the shape of the animal's head. The specific name *tenerensis* is after the Ténéré Desert where the animal was found.

MNN GDF500 is the holotype that was found in the Tegama Beds of the Elrhaz Formation. The holotype consists of a partial skeleton lacking the skull, but does have three neck ribs, ten dorsal ribs, parts of fourteen dorsal (back) vertebrae, gastralia (or "belly ribs"), pieces of three sacral vertebrae, parts of twelve caudal (tail) vertebrae, chevrons , a scapula (shoulder blade), a coracoid, a partial forelimb, most of the pelvis (hip bone), and parts of a hindlimb. The spinal column was greatly articulated, the remainder consisted of disarticulated bones. Parts of the skeleton had been exposed on the desert surface and had erosion damage. Additionally, several specimens have been assigned as paratypes: MNN GDF 501 to 508 include a snout, a quadrate from the back of the skull, three dentaries (tooth-bearing bones of the lower jaw), an axis (second neck vertebra), a rear cervical vertebra, and a rear dorsal vertebra. MNN GDF 510 to MNN GDF 511 comprise two caudal vertebrae. All original *Suchomimus* fossils are housed in the palaeontological collection of the Musée National du Niger. The first description of *Suchomimus* was preliminary. In 2007, the furcula (wishbone)—found during an expedition in 2000—was described in detail.

Suchomimus is potentially a junior synonym of of another spinosaurid from the Elrhaz Formation, *Cristatusaurus lapparenti.* It was named the same year based on jaw fragments and vertebrae. Skull elements were considered indistinguishable from those of *Baryonyx.* In 1997 whilst describing *S.* *tenerensis* Sereno and colleagues agreed with this assessment and concluded that *Cristatusaurus* was a dubious name. Later in 2002, the German palaeontologist Hans-Dieter Sues and colleagues concluded that *Suchomimus* was identical to *Cristatusaurus lapparenti*, and despite *Cristatusaurus* having been named somewhat earlier than *Suchomimus*, proposed them to represent a second species of *Baryonyx* called *Baryonyx tenerensis*. In a 2003 analysis, German paleontologist Oliver Rauhut concurred with this.

## Description

After discovering new specimens of *Carcharodontosaurus* and *Sarcosuchus*, Chicago-based paleontologist Paul Sereno and his team added a discovery in 1997. In the Sahara, near the Tenere Desert in Niger, they found fossils that represented about two-thirds of the skeleton of a huge meat-eater in the Tegama Bed of the Elrhaz Formation. This was named *Suchomimus* ("crocodile mimic") after the shape of its head. Its species name comes from the Tenere desert near where it as found. This led scientists to realize that spinosaurus may have actually had a crocodilian like snout, and in 2001 the spino snout was unearthed. This means *Suchomimus* is a major milestone to the appearance of Spinosaurus.

In a study from 2021, Rowe and Snively estimated a bite force of 4,037 Newtons (~400kg) for Suchomimus.

A 2022 research conducted by Nizar Ibrahim has indicated that this particular Spinosaurid Theropod species had the assumed features for a more Terrestrial or land based life style.

According to a scientific study officially published in 2023; Spinosauridae families; in particular specimens taken as exemplary samples and clade representatives from Baryonychidae; shows their brain anatomy and skull cavity structure shows no identifiable differentiation or any significant deviation from other common Theropod clades; particularly megalosauridae . The results interpreted as these theropods; presumably, showing similar behavior and traits with other general theropods in terms of brain structure and behavior.

Commenting on the results, lead-author of the study, PhD student Chris Barker (University of Southampton), stated:

*“Despite their unusual ecology, it seems the brains and senses of these early spinosaurs retained many aspects in common with other large-bodied theropods – there is no evidence that their semi-aquatic lifestyles are reflected in the way their brains are organised.”*

## Classification

The describers established some autapomorphies (unique derived traits) of *Suchomimus* to separate it from other theropods, including the expanded rear dorsal, sacral, and front caudal neural spines, the robust upper corners of the humerus, and the boss above the humerus' condyle that contacted its hook-shaped radius. Sereno and colleagues referred *Suchomimus* to the Spinosauridae and named two subfamilies within this clade, Baryonychinae (all spinosaurids more closely related to *Baryonyx*) and Spinosaurinae (all spinosaurids closer to *Spinosaurus*). *Suchomimus* was a member of the subfamily Baryonychinae. Apart from its apparently taller sail, *Suchomimus* was very similar to the spinosaurid *Baryonyx* from the Barremian of England, and shared traits with it such as the reduced size and increased amount of teeth behind the snout tip in the mandible than spinosaurines, strong forelimbs, a huge sickle-curved claw on its "thumb", and strongly keeled front dorsal vertebrae. Spinosaurines are characterized by straight, unserrated and more widely spaced teeth, and the small size of their first premaxillary teeth. Sereno and colleagues pointed out that the more retracted nostrils in *Irritator* and the tall sail of *Spinosaurus* could also be unique traits of spinosaurines, though material from other taxa is needed to know for sure. As with *Suchomimus*, the claw of *Baryonyx* had been the first discovered fossil of the animal. Sereno and colleagues in 1998 analyzed the distribution of forty-five traits to produce a cladogram that showed *Suchomimus* and *Baryonyx* to be distinct but closely related. Later, Bark and colleagues, in 2021, created a new tribe within Baryonychinae: Ceratosuchopsini, a clade that includes *Ceratosuchops*, *Riparovenator* and *Suchomimus*.

The following phylogenetic tree shows a 2009 analysis of the Megalosauroidea.

### Evolution

Spinosaurids appear to have been widespread from the Barremian to the Cenomanian stages of the Cretaceous period, about 130 to 95 million years ago, while the oldest known spinosaurid remains date to the Middle Jurassic. They shared features such as long, narrow, crocodile-like skulls; sub-circular teeth, with fine to no serrations; the terminal rosette of the snout; and a secondary palate that made them more resistant to torsion. In contrast, the primitive and typical condition for theropods was a tall, narrow snout with blade-like (ziphodont) teeth with serrated carinae. The skull adaptations of spinosaurids converged with those of Crocodilians; early members of the latter group had skulls similar to typical theropods, later developing elongated snouts, conical teeth, and secondary palates. These adaptations may have been the result of a dietary change from terrestrial prey to fish. Unlike crocodiles, the post-cranial skeletons of baryonychine spinosaurids do not appear to have aquatic adaptations. Sereno and colleagues proposed in 1998 that the large thumb-claw and robust forelimbs of spinosaurids evolved in the Middle Jurassic, before the elongation of the skull and other adaptations related to fish-eating, since the former features are shared with their megalosaurid relatives. They also suggested that the spinosaurines and baryonychines diverged before the Barremian age of the Early Cretaceous.

Several hypotheses have been proposed about the biogeography of the spinosaurids. Since *Suchomimus* was more closely related to *Baryonyx* (from Europe) than to *Spinosaurus*—although that genus also lived in Africa—the distribution of spinosaurids cannot be explained as vicariance resulting from continental rifting. Sereno and colleagues proposed that spinosaurids were initially distributed across the supercontinent Pangea, but split with the opening of the Tethys Sea. Spinosaurines would then have evolved in the south (Africa and South America: in Gondwana) and baryonychines in the north (Europe: in Laurasia), with *Suchomimus* the result of a single north-to-south dispersal event. Buffetaut and the Tunisian palaeontologist Mohamed Ouaja also suggested in 2002 that baryonychines could be the ancestors of spinosaurines, which appear to have replaced the former in Africa. Milner suggested in 2003 that spinosaurids originated in Laurasia during the Jurassic, and dispersed via the Iberian land bridge into Gondwana, where they radiated. In 2007, Buffetaut pointed out that palaeogeographical studies had demonstrated that Iberia was near northern Africa during the Early Cretaceous, which he found to confirm Milner's idea that the Iberian region was a stepping stone between Europe and Africa, which is supported by the presence of baryonychines in Iberia. The direction of the dispersal between Europe and Africa is still unknown, and subsequent discoveries of spinosaurid remains in Asia and possibly Australia indicate that it may have been complex. The findings of Barker et al. (2021) are consistent with Milner's findings, where Spinosauridae arose in Europe and there were at least two migrations to Africa.

## JPInstitute.com Description

Suchomimus was very similar to Spinosaurus, but it didn't have the tall sail on its back. Along with its cousin, Suchomimus ate mostly fish, which it caught with its long, thin snout full of sharp, cone-shaped teeth. It was discovered in 1998 and has given scientists a much clearer picture of what this fish-eating family of dinosaurs, which also includes Baryonyx, was like.

The discovery of Suchomimus has helped both scientists and the general public understand the rich diversity of life that lived in Africa millions of years ago. It has also provided scientist with valuable clues about the migration of the spinosaurs from Europe into Africa. Although it did not have nearly as prominent a sail as Spinosaurus, Suchomimus did have sacral vertebrae that supported a two-foot (.7 m) sail on its back. Some scientists are questioning whether this dinosaur is a unique genus or if it might be a species of Baryonyx.

## Dinosaur Field Guide Description

Suchomimus ("crocodile mimic") is spinosaur dinosaur, related to Baryonyx and Spinosaurus. Like them, it had a long, narrow snout packed with crocodile-like teeth and a huge thumb claw. Although it was larger than Baryonyx, it was smaller than the gigantic Spinosaurus. Suchomimus was given the name "crocodile mimic" because, like a crocodile, its skull was long and slender and its teeth were shaped like cones (unlike
many of the meat-eaters, which had blade-like teeth). Some paleontologists think that this means they ate mostly fish. It is true that Suchomimus lived near water, and that the remains of 10-foot (3-m) fish were found with it in the same rocks. This suggests that Suchomimus waded into the water and grabbed fish with its jaws, or hooked them with its thumb claw. Today's big crocodilians eat both large fish and land animals. Suchomimus, too, could have hunted the big land animals of its day-other dinosaurs. Its jaws could kill a dinosaur as easily as they could a fish.

### Fun Facts

Another dinosaur from the same rock formation as Suchomimus is the sailbacked Ouranosaurus, a relative of Iguanodon.

### Trivia

The thumb claw was one of the first bones found for both Baryonyx and Suchomimus.

## Appearance in other media

### *Jurassic Park*

* It was also mentioned in *Jurassic Park III* when Billy tried to identify the *Spinosaurus*, which was the primary antagonist of the movie.

* *Suchomimus* appeared on the website for *Jurassic World*, but unfortunately didn't appear in the actual movie.

* While not in the trailers so far, it has been revealed that there are surviving *Suchomimus* populations on Isla Nublar, but they and many other dinosaurs will now face an impending danger in the form of an erupting volcano in *Jurassic World: Fallen Kingdom*. It is possible that some Suchomimus was saved offscreen. Since some teeth can be shown in Ken Whealty's tooth bag meaning the species survived.

* *Suchomimus* is in *Jurassic World: Alive*. It seems to be based on the *Jurassic World* website design.

* *Suchomimus* is one of five dinosaurs that are available in deluxe edition of *Jurassic World: Evolution* It seems to be based on the *Jurassic World* website design.

* It also appears in Jurassic World: The Game as a legendary carnivore. Since January 11th, 2016, a fully maxed *Suchomimus* can be hybrid-ed with a fully maxed *Dsungaripterus* to make the hybrid ***Suchoripterus***.

* It also appears in Jurassic Park Builder as a DNA tournament dinosaur.

* It also appears in it's 1st PlayStation Game Warpath: Jurassic Park.

## Links

http://web.archive.org/web/20040420191321fw\_/http://www.jpinstitute.com/dinopedia/dinocards/dc\_sucho.html

1. ↑ https://pubmed.ncbi.nlm.nih.gov/36781174/
2. ↑ https://onlinelibrary.wiley.com/doi/10.1111/joa.13837
3. ↑ https://blog.everythingdinosaur.com/blog/\_archives/2023/02/14/spinosaurs-modified-skulls-but-conservative-brains.html