Suchomimus

***Suchomimus*** (meaning "crocodile mimic") is a genus of spinosaurid dinosaur that lived between 125 and 112 million years ago in what is now Niger, during the Aptian to early Albian stages of the Early Cretaceous period. The animal was named and described by palaeontologist Paul Sereno and colleagues in 1998, based on a partial skeleton from the Elrhaz Formation. *Suchomimus*'s long and shallow skull, similar to that of a crocodile, earns it its generic name, while the specific name ***Suchomimus tenerensis*** alludes to the locality of its first remains, the Ténéré Desert.

*Suchomimus* was 9.5 to 11 metres (31 to 36 feet) long and weighed between 2.5 to 5.2 tonnes (2.8 to 5.7 short tons), although the holotype specimen may not have been fully grown. *Suchomimus*'s narrow skull was perched on a short neck, and its forelimbs were powerfully built, bearing a giant claw on each thumb. Along the midline of the animal's back ran a low dorsal sail, built from the long neural spines of its vertebrae. Like other spinosaurids, it likely had a diet of fish and small prey animals.

Some palaeontologists consider the animal to be an African species of the European spinosaurid *Baryonyx*, *B. tenerensis*. *Suchomimus* might also be a junior synonym of the contemporaneous spinosaurid *Cristatusaurus lapparenti*, although the latter taxon is based on much more fragmentary remains. *Suchomimus* lived in a fluvial environment of vast floodplains alongside many other dinosaurs, in addition to pterosaurs, crocodylomorphs, fish, turtles, and bivalves.

## Description

The length of the type specimen of *Suchomimus*, a subadult, was initially estimated at 10.3–11 metres (34–36 feet), with an estimated weight of between 2.7–5.2 tonnes (3.0–5.7 short tons; 2.7–5.1 long tons). Gregory S. Paul, however, gave lower estimations of 9.5 m (31 ft) and 2.5 t (2.8 short tons; 2.5 long tons). The holotype of *Suchomimus* was considerably larger than that of *Baryonyx*, but the ages of the two individuals are not known.

### Skull

Unlike most giant theropod dinosaurs, *Suchomimus* had a very crocodilian-like skull, with a long, low snout and narrow jaws formed by a forward expansion of the premaxillae (frontmost snout bones) and the hind branch of the maxillae (main upper jaw bone). The premaxillae had an upward branch excluding the maxillae from the external nares (bony nostrils). The jaws had about 122 conical teeth, pointed but not very sharp and curving slightly backwards, with fine serrations and wrinkled enamel. The tip of the snout was enlarged sideways and carried a "terminal rosette" of longer teeth, seven per side in the premaxillae and about the same number in the corresponding part of the lower jaw. Further back, there were at least 22 teeth per upper jaw side in the maxilla, while the entire lower jaw side carried 32 teeth in the dentary bone.

### Postcranial skeleton

The upper jaw had a prominent kink just behind the rosette, protruding downwards; this convexly curved part of the maxilla had the longest teeth of the entire skull. The internal bone shelves of the maxillae met each other in the midline of the skull over a long distance, forming a closed secondary palate that stiffened the snout, and setting off the internal nostrils and palatal complex (including the pterygoid, palatine and ectopterygoid) towards the back of the skull. The nostrils, unlike in most theropods, were retracted further back on the skull and behind the premaxillary teeth. The external nares were long, narrow and horizontally positioned; the same was true of the larger antorbital fenestrae, a pair of bony openings in front of the eyes. The rear of the skull is poorly known but for a short quadrate bone, which had broad condyles (round protrusions) away from the centre of attachment and—like in the spinosaurid *Baryonyx*—had a large foramen (opening) separating it from the quadratojugal bone. The lower jaws were greatly elongated and narrow, forming a rigid structure as their dentaries touched each other at the midline, reinforcing the mandible against torsional (bending and twisting) forces.

## *Suchomimus* from The Amazing Dinosaur Adventure

*Suchomimus* from *The Secret of Saurus Rock**Suchomimus* as it appeared in *The Lone Dinosaur Returns* in a flashback