Bady the Baryonyx

Bady the Baryonyxs

## Bady

Bady is a Baryonyx has a colored body Light Blue with Stripes Dark Blue and White Belly

Bady is Baryonyx Gooding age 17 we Have Teen Baryonyx

Bady Eating Food Such As Fish Sallmon Trout

## Information

***Baryonyx*** (/ˌbæriˈɒnɪks/) is a genus of theropod dinosaur which lived in the Barremian stage of the Early Cretaceous period, about 130–125 million years ago. The first skeleton was discovered in 1983 in the Smokejack Clay Pit, of Surrey, England, in sediments of the Weald Clay Formation, and became the holotype specimen of ***Baryonyx walkeri***, named by palaeontologists Alan J. Charig and Angela C. Milner in 1986. The generic name, *Baryonyx*, means "heavy claw" and alludes to the animal's very large claw on the first finger; the specific name, *walkeri*, refers to its discoverer, amateur fossil collector William J. Walker. The holotype specimen is one of the most complete theropod skeletons from the UK (and remains the most complete Spinosaurid), and its discovery attracted media attention. Specimens later discovered in other parts of the United Kingdom and Iberia have also been assigned to the genus, though many have since been moved to new genera.

The holotype specimen, which may not have been fully grown, was estimated to have been between 7.5 and 10 metres (25 and 33 feet) long and to have weighed between 1.2 and 2 metric tons (1.3 and 2.2 short tons; 1.2 and 2.0 long tons). *Baryonyx* had a long, low, and narrow snout, which has been compared to that of a gharial. The tip of the snout expanded to the sides in the shape of a rosette. Behind this, the upper jaw had a notch which fitted into the lower jaw (which curved upwards in the same area). It had a triangular crest on the top of its nasal bones. *Baryonyx* had a large number of finely serrated, conical teeth, with the largest teeth in front. The neck formed an S-shape, and the neural spines of its dorsal vertebrae increased in height from front to back. One elongated neural spine indicates it may have had a hump or ridge along the centre of its back. It had robust forelimbs, with the eponymous first-finger claw measuring about 31 centimetres (12 inches) long.

Now recognised as a member of the family Spinosauridae, *Baryonyx*'s affinities were obscure when it was discovered. Some researchers have suggested that *Suchosaurus cultridens* is a senior synonym (being an older name), and that *Suchomimus tenerensis* belongs in the same genus; subsequent authors have kept them separate. *Baryonyx* was the first theropod dinosaur demonstrated to have been piscivorous (fish-eating), as evidenced by fish scales in the stomach region of the holotype specimen. It may also have been an active predator of larger prey and a scavenger, since it also contained bones of a juvenile iguanodontid. The creature would have caught and processed its prey primarily with its forelimbs and large claws. *Baryonyx* may have had semi-aquatic habits, and coexisted with other theropod, ornithopod, and sauropod dinosaurs, as well as pterosaurs, crocodiles, turtles and fishes, in a fluvial environment.

## History of discovery[edit]

In January 1983, the plumber and amateur fossil collector William J. Walker explored the Smokejack Clay Pit, a clay pit in the Weald Clay Formation near Ockley in Surrey, England. He found a rock wherein he discovered a large claw, but after piecing it together at home, he realised the tip of the claw was missing. Walker returned to the same spot in the pit some weeks later, and found the missing part after searching for an hour. He also found a phalanx bone and part of a rib. Walker's son-in-law later brought the claw to the Natural History Museum of London, where it was examined by the palaeontologists Alan J. Charig and Angela C. Milner, who identified it as belonging to a theropod dinosaur.[1][2] The palaeontologists found more bone fragments at the site in February, but the entire skeleton could not be collected until May and June due to weather conditions at the pit.[3][2] A team of eight museum staff members and several volunteers excavated 2 metric tons (2.2 short tons; 2.0 long tons) of rock matrix in 54 blocks over a three-week period. Walker donated the claw to the museum, and the Ockley Brick Company (owners of the pit) donated the rest of the skeleton and provided equipment.[3][4][2] The area had been explored for 200 years, but no similar remains had been found before.[5][2]

Most of the bones collected were encased in siltstone nodules surrounded by fine sand and silt, with the rest lying in clay. The bones were disarticulated and scattered over a 5-by-2-metre (16.4-by-6.6-foot) area, but most were not far from their natural positions. The position of some bones was disturbed by a bulldozer, and some were broken by mechanical equipment before they were collected.[3][1][6] Preparing the specimen was difficult, due to the hardness of the siltstone matrix and the presence of siderite; acid preparation was attempted, but most of the matrix was removed mechanically. It took six years of almost constant preparation to get all the bones out of the rock, and by the end, dental tools and air mallets had to be used under a microscope. The specimen represents about 65 per cent of the skeleton, and consists of partial skull bones, including premaxillae (first bones of the upper jaw); the left maxillae (second bone of the upper jaw); both nasal bones; the left lacrimal; the left prefrontal; the left postorbital; the braincase including the occiput; both dentaries (the front bones of the lower jaw); various bones from the back of the lower jaw; teeth; cervical (neck), dorsal (back), and caudal (tail) vertebrae; ribs; a sternum; both scapulae (shoulder blades); both coracoids; both humeri (upper arm bones); the left radius and ulna (lower arm bones); finger bones and unguals (claw bones); hip bones; the upper end of the left femur (thigh bone) and lower end of the right; right fibula (of the lower leg); and foot bones including an ungual.[3][1][7][2] The original specimen number was BMNH R9951, but it was later re-catalogued as NHMUK VP R9951.[1][8]

https://upload.wikimedia.org/wikipedia/commons/thumb/5/54/Baryonyx\_snout\_and\_other\_skeletal\_elements.jpg/94px-Baryonyx\_snout\_and\_other\_skeletal\_elements.jpg

https://upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Baryonyx\_fossil\_elements.jpg/95px-Baryonyx\_fossil\_elements.jpg

https://upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Postcranial\_skeletal\_elements\_of\_Baryonyx.jpg/91px-Postcranial\_skeletal\_elements\_of\_Baryonyx.jpg

https://upload.wikimedia.org/wikipedia/commons/thumb/c/cb/Baryonyx\_NHM.jpg/288px-Baryonyx\_NHM.jpg

Skeletal elements of the holotype specimen as archived (above), and reconstructed skeleton on exhibit (below), in Natural History Museum, London

In 1986, Charig and Milner named a new genus and species with the skeleton as holotype specimen: *Baryonyx walkeri*. The generic name derives from ancient Greek; βαρύς (*barys*) means "heavy" or "strong", and ὄνυξ (*onyx*) means "claw" or "talon". The specific name honours Walker, for discovering the specimen. At that time, the authors did not know if the large claw belonged to the hand or the foot (as in dromaeosaurs, which it was then assumed to be[9]). The dinosaur had been presented earlier the same year during a lecture at a conference about dinosaur systematics in Drumheller, Canada. Due to ongoing work on the bones (70 per cent had been prepared at the time), they called their article preliminary and promised a more detailed description at a later date. *Baryonyx* was the first large Early Cretaceous theropod found anywhere in the world by that time.[1][6] Before the discovery of *Baryonyx* the last significant theropod find in the United Kingdom was *Eustreptospondylus* in 1871, and in a 1986 interview Charig called *Baryonyx* "the best find of the century" in Europe.[3][4] *Baryonyx* was widely featured in international media, and was nicknamed "Claws" by journalists punning on the title of the film *Jaws*. Its discovery was the subject of a 1987 BBC documentary, and a cast of the skeleton is mounted at the Natural History Museum in London. In 1997, Charig and Milner published a monograph describing the holotype skeleton in detail.[3][5][10] The holotype specimen remains the most completely known spinosaurid skeleton.[11]

### Assigned specimens[edit]

Fossils from other parts of the UK and Iberia, mostly isolated teeth, have subsequently been attributed to *Baryonyx* or similar animals.[3] Isolated teeth and bones from the Isle of Wight, including hand bones reported in 1998 and a vertebra reported by the palaeontologists Steve Hutt and Penny Newbery in 2004, have been attributed to this genus.[12] A maxilla fragment from La Rioja, Spain, was attributed to *Baryonyx* by the palaeontologists Luis I. Viera and José Angel Torres in 1995[13] (although the palaeontologist Thomas R. Holtz and colleagues raised the possibility that it could have belonged to *Suchomimus* in 2004).[14] In 1999, a postorbital, squamosal, tooth, vertebral remains, metacarpals (hand bones), and a phalanx from the Salas de los Infantes deposit in Burgos Province, Spain, were attributed to an immature *Baryonyx* (though some of these elements are unknown in the holotype) by the palaeontologist Carolina Fuentes Vidarte and colleagues.[15][16] Dinosaur tracks near Burgos have also been suggested to belong to *Baryonyx* or a similar theropod.[17]In 2011, a specimen (Catalogued as ML1190 in Museu da Lourinhã) from the Papo Seco Formation in Boca do Chapim, Portugal, with a fragmentary dentary, teeth, vertebrae, ribs, hip bones, a scapula, and a phalanx bone, was attributed to *Baryonyx* by the palaeontologist Octávio Mateus and colleagues, the most complete Iberian remains of the animal. The skeletal elements of this specimen are also represented in the more complete holotype (which was of similar size), except for the mid-neck vertebrae.[18] In 2018, the palaeontologist Thomas M. S. Arden and colleagues found that the Portuguese skeleton did not belong to *Baryonyx*, since the front of its dentary bone was not strongly upturned.[19] This specimen was made the basis of the new genus *Iberospinus* by Mateus and Darío Estraviz-López in 2022.[20] Additional spinosaurid remains from Iberia may belong to taxa other than *Baryonyx*, such as *Vallibonavenatrix* and *Protathlitis*, or may be indeterminate.[21][22][23][24]

In 2021, the palaeontologist Chris T. Barker and colleagues described two new spinosaurid genera from the Wessex Formation of the Isle of Wight, *Ceratosuchops* and *Riparovenator* (the latter named *R. milnerae* honouring Milner for her contributions to spinosaurid research), and stated that spinosaurid material from there that had previously been attributed to the contemporary *Baryonyx* could have belonged to other taxa instead.[25] These specimens had previously been assigned to *Baryonyx* in a 2017 conference abstract.[26] Barker and colleagues stated that the recognition of the Wessex Formation specimens as new genera renders the presence of *Baryonyx* there ambiguous, and most of the previously assigned isolated material from the Wealden Supergroup is therefore indeterminate.[25] A 2023 study of an isolated tooh by Barker and colleagues found that it and other teeth from the Wealden Supergroup that have previously been assigned to *Baryonyx* probably do not belong to the genus, based on their morphology and age.[27]

### Possible synonyms[edit]

https://upload.wikimedia.org/wikipedia/commons/thumb/3/3e/Suchosaurus.jpg/122px-Suchosaurus.jpg

https://upload.wikimedia.org/wikipedia/commons/thumb/0/03/Suchosaurus\_cultridens\_holotype\_tooth.jpg/162px-Suchosaurus\_cultridens\_holotype\_tooth.jpg

1878 lithograph (left) and modern photo showing the holotype tooth of *Suchosaurus cultridens*, which may represent the same animal as *B. walkeri*

In 2003, Milner noted that some teeth at the Natural History Museum previously identified as belonging to the genera *Suchosaurus* (the first named spinosaurid) and *Megalosaurus* probably belonged to *Baryonyx*.[7][28] The type species of *Suchosaurus*, *S. cultridens*, was named by the biologist Richard Owen in 1841, based on teeth discovered by the geologist Gideon A. Mantell in Tilgate Forest, Sussex. Owen originally thought the teeth to have belonged to a crocodile; he was yet to name the group Dinosauria, which happened the following year. A second species, *S. girardi*, was named by the palaeontologist Henri Émile Sauvage in 1897, based on jaw fragments and a tooth from Boca do Chapim, Portugal. In 2007, the palaeontologist Éric Buffetaut considered the teeth of *S. girardi* very similar to those of *Baryonyx* (and *S. cultridens*) except for the stronger development of the tooth crown flutes (or "ribs"; lengthwise ridges), suggesting that the remains belonged to the same genus. Buffetaut agreed with Milner that the teeth of *S. cultridens* were almost identical to those of *B. walkeri*, but with a ribbier surface. The former taxon might be a senior synonym of the latter (since it was published first), depending on whether the differences were within a taxon or between different ones. According to Buffetaut, since the holotype specimen of *S. cultridens* is a single tooth and that of *B. walkeri* is a skeleton, it would be more practical to retain the newer name.[29][30][31] In 2011, Mateus and colleagues agreed that *Suchosaurus* was closely related to *Baryonyx*, but considered both species in the former genus *nomina dubia* (dubious names) since their holotype specimens were not considered diagnostic (lacking distinguishing features) and could not be definitely equated with other taxa.[18] Barker and colleagues agreed with this in 2023.[27]In 1997, Charig and Milner noted that two fragmentary spinosaurid snouts from the Elrhaz Formation of Niger (reported by the palaeontologist Philippe Taquet in 1984) were similar enough to *Baryonyx* that they considered them to belong to an indeterminate species of the genus (despite their much younger Aptian geological age).[3] In 1998, these fossils became the basis of the genus and species *Cristatusaurus lapparenti*, named by Taquet and the palaeontologist Dale Russell.[32] The palaeontologist Paul Sereno and colleagues named the new genus and species *Suchomimus tenerensis* later in 1998, based on more complete fossils from the Elrhaz Formation. In 2002, the German palaeontologist Hans-Dieter Sues and colleagues proposed that *Suchomimus tenerensis* was similar enough to *Baryonyx walkeri* to be considered a species within the same genus (as *B. tenerensis*), and that *Suchomimus* was identical to *Cristatusaurus*.[33] Milner concurred that the material from Niger was indistinguishable from *Baryonyx* in 2003.[7] In a 2004 conference abstract, Hutt and Newberry supported the synonymy based on a large theropod vertebra from the Isle of Wight which they attributed to an animal closely related to *Baryonyx* and *Suchomimus*.[34] Later studies have kept *Baryonyx* and *Suchomimus* separate, whereas *Cristatusaurus* has been proposed to be either a *nomen dubium* or possibly distinct from both.[18][35][36][37][38] A 2017 review paper by the palaeontologist Carlos Roberto A. Candeiro and colleagues stated that this debate was more in the realm of semantics than science, as it is generally agreed that *B. walkeri* and *S. tenerensis* are distinct, related species.[39] Barker and colleagues found *Suchomimus* to be closer related to the British genera *Riparovenator* and *Ceratosuchops* than to *Baryonyx* in 2021.[25]

## Description[edit]

*Baryonyx* is estimated to have been between 7.5 and 10 m (25 and 33 ft) long, 2.5 m (8.2 ft) in hip height, and to have weighed between 1.2 and 2 t (1.3 and 2.2 short tons; 1.2 and 2.0 long tons). The fact that elements of the skull and vertebral column of the *B. walkeri* holotype specimen (NHM R9951) do not appear to have co-ossified (fused) suggests that the individual was not fully grown, and the mature animal may have been much larger (as is the case for some other spinosaurids). On the other hand, the specimen's fused sternum indicates that it may have been mature.[3][40][41][42]

### Skull[edit]

https://upload.wikimedia.org/wikipedia/commons/thumb/7/75/Baryonyx\_walkeri\_rostrum.png/200px-Baryonyx\_walkeri\_rostrum.png

Snout of the holotype specimen, from the left and below

https://upload.wikimedia.org/wikipedia/commons/thumb/7/73/Baryonyx\_dentary.jpg/200px-Baryonyx\_dentary.jpg

Holotype dentary from the left

The skull of *Baryonyx* is incompletely known, and much of the middle and hind portions are not preserved. The full length of the skull is estimated to have been 91–95 centimetres (36–37 inches) long, based on comparison with that of the related genus *Suchomimus* (which was 20% larger).[3][37] It was elongated, and the front 17 cm (6.7 in) of the premaxillae formed a long, narrow, and low snout (rostrum) with a smoothly rounded upper surface.[3] The external nares (bony nostrils) were long, low, and placed far back from the snout tip. The front 13 cm (5.1 in) of the snout expanded into a spatulate (spoon-like), "terminal rosette", a shape similar to the rostrum of the modern gharial. The front 7 cm (2.8 in) of the lower margin of the premaxillae was downturned (or hooked), whereas that of the front portion of the maxillae was upturned. This morphology resulted in a sigmoid or S shaped margin of the lower upper tooth row, in which the teeth from the front of the maxilla were projecting forward. The snout was particularly narrow directly behind the rosette; this area received the large teeth of the mandible. The maxilla and premaxilla of *Baryonyx* fit together in a complex articulation, and the resulting gap between the upper and lower jaw is known as the subrostral notch.[3] A downturned premaxilla and a sigmoid lower margin of the upper tooth row was also present in distantly related theropods such as *Dilophosaurus*. The snout had extensive foramina (openings), which would have been exits for blood vessels and nerves,[3] and the maxilla appears to have housed sinuses.[3][37][41]*Baryonyx* had a rudimentary secondary palate, similar to crocodiles but unlike most theropod dinosaurs.[43] A rugose (roughly wrinkled) surface suggests the presence of a horny pad in the roof of the mouth. The nasal bones were fused, which distinguished *Baryonyx* from other spinosaurids, and a sagittal crest was present above the eyes, on the upper mid-line of the nasals. This crest was triangular, narrow, and sharp in its front part, and was distinct from those of other spinosaurids in ending hind wards in a cross-shaped process. The lacrimal bone in front of the eye appears to have formed a horn core similar to those seen, for example, in *Allosaurus*, and was distinct from other spinosaurids in being solid and almost triangular. The occiput was narrow, with the paroccipital processes pointing outwards horizontally, and the basipterygoid processes were lengthened, descending far below the basioccipital (the lowermost bone of the occiput).[3][41][44] Sereno and colleagues suggested that some of *Baryonyx*'s cranial bones had been misidentified by Charig and Milner, resulting in the occiput being reconstructed as too deep, and that the skull was instead probably as low, long and narrow as that of *Suchomimus*.[44] The front 14 cm (5.5 in) of the dentary in the mandible sloped upwards towards the curve of the snout. The dentary was very long and shallow, with a prominent Meckelian groove on the inner side. The mandibular symphysis, where the two halves of the lower jaw connected at the front, was particularly short. The rest of the lower jaw was fragile; the hind third was much thinner than the front, with a blade-like appearance. The front part of the dentary curved outwards to accommodate the large front teeth, and this area formed the mandibular part of the rosette. The dentary–like the snout—had many foramina.[3][37]Most of the teeth found with the holotype specimen were not in articulation with the skull; a few remained in the upper jaw, and only small replacement teeth were still borne by the lower jaw. The teeth had the shape of recurved cones, where slightly flattened from sideways, and their curvature was almost uniform. The roots were very long, and tapered towards their extremity.[3] The carinae (sharp front and back edges) of the teeth were finely serrated with denticles on the front and back, and extended all along the crown. There were around six to eight denticles per mm (0.039 in), a much larger number than in large-bodied theropods like *Torvosaurus* and *Tyrannosaurus*. Some of the teeth were fluted, with six to eight ridges along the length of their inner sides and fine-grained enamel (outermost layer of teeth), while others bore no flutes; their presence is probably related to position or ontogeny (development during growth).[3][37] The inner side of each tooth row had a bony wall. The number of teeth was large compared to most other theropods, with six to seven teeth in each premaxilla and thirty-two in each dentary. Based on the closer packing and smaller size of the dentary teeth compared to those in the corresponding length of the premaxilla, the difference between the number of teeth in the upper and lower jaws appears to have been more pronounced than in other theropods.[3] The terminal rosette in the upper jaw of the holotype had thirteen dental alveoli (tooth sockets), six on the left and seven on the right side, showing tooth count asymmetry. The first four upper teeth were large (with the second and third the largest), while the fourth and fifth progressively decreased in size.[3] The diameter of the largest was twice that of the smallest. The first four alveoli of the dentary (corresponding to the tip of the upper jaw) were the largest, with the rest more regular in size. Small subtriangular interdental plates were present between the alveoli.[3][37]

### Postcranial skeleton[edit]

https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Baryonyx\_neck\_vertebrae.png/188px-Baryonyx\_neck\_vertebrae.png

https://upload.wikimedia.org/wikipedia/commons/thumb/4/41/Neck\_reconstructions\_of\_Sigilmassasaurus\_and\_Baryonyx.png/96px-Neck\_reconstructions\_of\_Sigilmassasaurus\_and\_Baryonyx.png

Three cervical vertebrae from the neck of the holotype in left side view, the third also shown from the front (left), and reconstructed necks of the spinosaurids *Sigilmassasaurus* (A) and *Baryonyx* (B), showing their curvature (right)

Initially thought to have lacked the sigmoid curve typical of theropods,[3] the neck of *Baryonyx* does appear to have formed an S shape, though straighter than in other theropods.[45] The cervical vertebrae of the neck tapered towards the head and became progressively longer front to back. Their zygapophyses (the processes that connected the vertebrae) were flat, and their epipophyses (processes to which neck muscles attached) were well developed. The axis (the second neck vertebra) was small relative to the size of the skull and had a well-developed hyposphene. The neural arches of the cervical vertebrae were not always sutured to the centra (the bodies of the vertebrae), and the neural spines there were low and thin. The cervical ribs were short, similar to those of crocodiles, and possibly overlapped each other somewhat. The centra of the dorsal vertebrae of the back were similar in size. Like in other theropods, the skeleton of *Baryonyx* showed skeletal pneumaticity, reducing its weight through fenestrae (openings) in the neural arches and pleurocoels (hollow depressions) in the centra (primarily near the transverse processes). From front to back, the neural spines of the dorsal vertebrae changed from short and stout to tall and broad. One isolated dorsal neural spine was moderately elongated and slender, indicating that *Baryonyx* may have had a hump or ridge along the centre of its back (though incipiently developed compared to those of other spinosaurids). *Baryonyx* was unique among spinosaurids in having a marked constriction from side to side in a vertebra that either belonged to the sacrum or front of the tail.[3][6][44]The coracoid tapered hind-wards when viewed in profile, and, uniquely among spinosaurids, connected with the scapula in a peg-and-notch articulation. The scapulae were robust and the bones of the forelimb were short in relation to the animal's size, but broad and sturdy. The humerus was short and stout, with its ends broadly expanded and flattened—the upper side for the deltopectoral crest and muscle attachment and the lower for articulation with the radius and ulna. The radius was short, stout and straight, and less than half the length of the humerus, while the ulna was a little longer. The ulna had a powerful olecranon and an expanded lower end. The hands had three fingers; the first finger bore a large claw measuring about 31 cm (12 in) along its curve in the holotype specimen. The claw would have been lengthened by a keratin (horny) sheath in life. Apart from its size, the claw's proportions were fairly typical of a theropod, i.e. it was bilaterally symmetric, slightly compressed, smoothly rounded, and sharply pointed. A groove for the sheath ran along the length of the claw. The other claws of the hand were much smaller. The ilium (main hip bone) of the pelvis had a prominent supracetabular crest, an anterior process that was slender and vertically expanded, and a posterior process that was long and straight. The ilium also had a prominent brevis shelf and a deep grove that faced downwards. The acetabulum (the socket for the femur) was long from front to back. The ischium (lower and rearmost hip bone) had a well developed obturator process at the upper part. The margin of the pubic blade at the lower end was turned outward, and the pubic foot was not expanded. The femur lacked a groove on the fibular condyle, and, uniquely among spinosaurids, the fibula had a very shallow fibular fossa (depression).[3][41][6][44]

## Classification[edit]

In their original description, Charig and Milner[1] found *Baryonyx* unique enough to warrant a new family of theropod dinosaurs: Baryonychidae. They found *Baryonyx* to be unlike any other theropod group, and considered the possibility that it was a thecodont (a grouping of early archosaurs now considered unnatural), due to having apparently primitive features,[1] but noted that the articulation of the maxilla and premaxilla was similar to that in *Dilophosaurus*. They also noted that the two snouts from Niger (which later became the basis of *Cristatusaurus*), assigned to the family Spinosauridae by Taquet in 1984, appeared almost identical to that of *Baryonyx* and they referred them to Baryonychidae instead.[1] In 1988, the palaeontologist Gregory S. Paul agreed with Taquet that *Spinosaurus*, described in 1915 based on fragmentary remains from Egypt that were destroyed in World War II, and *Baryonyx* were similar and (due to their kinked snouts) possibly late-surviving dilophosaurs.[42] Buffetaut also supported this relationship in 1989.[46] In 1990, Charig and Milner dismissed the spinosaurid affinities of *Baryonyx*, since they did not find their remains similar enough.[6] In 1997, they agreed that Baryonychidae and Spinosauridae were related, but disagreed that the former name should become a synonym of the latter, because the completeness of *Baryonyx* compared to *Spinosaurus* made it a better type genus for a family, and because they did not find the similarities between the two significant enough.[3] Holtz and colleagues listed Baryonychidae as a synonym of Spinosauridae in 2004.[14]

Discoveries in the 1990s shed more light on the relationships of *Baryonyx* and its relatives. In 1996, a snout from Morocco was referred to *Spinosaurus*, and *Irritator* and *Angaturama* from Brazil (the two are possible synonyms) were named.[47][33] *Cristatusaurus* and *Suchomimus* were named based on fossils from Niger in 1998. In their description of *Suchomimus*, Sereno and colleagues placed it and *Baryonyx* in the new subfamily Baryonychinae within Spinosauridae; *Spinosaurus* and *Irritator* were placed in the subfamily Spinosaurinae. Baryonychinae was distinguished by the small size and larger number of teeth in the dentary behind the terminal rosette, the deeply keeled front dorsal vertebrae, and by having serrated teeth. Spinosaurinae was distinguished by their straight tooth crowns without serrations, small first tooth in the premaxilla, increased spacing of teeth in the jaws, and possibly by having their nostrils placed further back and the presence of a deep neural spine sail.[44][32] They also united the spinosaurids and their closest relatives in the superfamily Spinosauroidea, but in 2010, the palaeontologist Roger Benson considered this a junior synonym of Megalosauroidea (an older name).[48] In a 2007 conference abstract, the palaeontologist Denver W. Fowler suggested that since *Suchosaurus* is the first named genus in its group, the clade names Spinosauroidea, Spinosauridae, and Baryonychinae should be replaced by Suchosauroidea, Suchosauridae, and Suchosaurinae, regardless of whether or not the name *Baryonyx* is retained.[28] A 2017 study by the palaeontologists Marcos A. F. Sales and Cesar L. Schultz found that the clade Baryonychinae was not well supported, since serrated teeth may be an ancestral trait among spinosaurids.[38]Barker and colleagues found support for a Baryonychinae-Spinosaurinae split in 2021, and the following cladogram shows the position of *Baryonyx* within Spinosauridae according to their study:[25]