Temporal range: Early–Late Cretaceous
|An artist's rendering of Spinosaurus aegyptiacus (artwork produced by paleoartist Mark Witton)|
Stromer et al., 1915
Spinosaurus aegyptiacus (the name meaning: "spined lizard") is an extinct genus of large spinosaurid theropod dinosaur that inhabited early to middle Cretaceous (Cenomanian) in Northern Africa, states such as Morocco, Egypt, Tunusia, Libya; approximately 112 to 93.5 million years ago. The first known remains were found in Egypt by the German paleontologist Ernst Stromer in 1912, then described and named in 1915. the original Holotype remains were destroyed in World War II in a bombing raid, in 1944 by the British RAF. Fortunately more Additional material from other individuals have been found and come to light in the 21st century, though lots of jaw pieces and other material are sold and kept in private collections, lost to science.
The contemporary spinosaurid genus Sigilmassasaurus has been synonymized by some authors with S. aegyptiacus, and more recently others proposed it to be a distinct taxon yet again with a new mid-cervical vertebra. However recent scientific publication does not synonymize Sigilmassasaurus with Spinosaurus.
Paleontologists David W.E. and Thomas R. Holtz, Jr. think that Spinosaurus was more akin to Generalist wading animal species instead of highly Specialized aquatic species in a recent paper. The interpretations arises from inconsistencies with the pursuit predator model by Ibraham et.al.
Spinosaurus were among the largest known of all carnivorous dinosaurs, estimated as either being the same size or bigger than Tyrannosaurus, Giganotosaurus, and Carcharodontosaurus. Several estimates published in 2005, 2007 and 2008 suggest it was 12.6-18 meters (41- 59 feet) long, and weighed between 7.7 to 23.0 short tons. In 2014 and 2018 new size estimates based on a more complete studies, suggest a weight of 7.1-8.3 short tons and a length of 49-53 feet (15-17 meters). The Newest estimates suggest a weight of 7.1 to 8.3 short tons.
The first remains have been officially discovered in Egypt in 1912 and named by paleontologist Ernst Stromer, in 1915 however, the original remains were destroyed in World War II. The name; Spinosaurus means, spine lizard in Latin. It gets its name from the sail on its Dorsal vertebrae.
Discovery and naming
Naming of species
Two species of Spinosaurus have been named: Spinosaurus aegyptiacus (meaning "Egyptian spined lizard") and the disputed Spinosaurus maroccanus (meaning "Moroccan spine lizard").
The current size estimations for Spinosaurus suggest a length estimation between 15 to 17 meters long  6 to 7 meters tall and weighted between 6.5 to 7.5 tonnes; albeit Nizar Ibrahim has acclaimed that the Spinosaurus could have likely attained more than 7 tons; between 9 to 12 tons.
The current, estimated, length of Spinosaurus is anywhere between 41 to 53 feet (12.6 to 17 meters). Since it's discovery, Spinosaurus has always been a contender for largest carnivorous theropod, in 1926 Friedrich von Huene and Donald F. Glut in 1982 listed it as among the most massive theropods in their surveys, thought to be 15 meters (49 feet) long and weigh 6.6 short tons. in 1988 Greg Paul also listed it as longest theropod at 15 meters (49 feet), but however gave it a lower mass estimate of 4.4 short tons.
17 years later in 2005, Dal Sasso and colleagues assumed that Spinosaurus had the same body proportions as Suchomimus and therefore calculated that Spinosaurus was 52 to 59 feet (16 to 18 meters) long and a weight of 7.7 to 9.9 short tons. But these estimates were criticized because the skull length estimate was uncertain, and (assuming that body mass increases as the cube of body length) scaling Suchomimus which was 11 meters (36 ft) long and 4.2 short tons in mass to the range of estimated lengths of Spinosaurus would produce an estimated body mass of 12.9 to 18.4 short tons.
François Therrien and Donald Henderson, in a 2007 paper used scaling based on skull length, challenged the previous size estimates of Spinosaurus finding the length too great and the weight too small. They instead calculated a body length of 12.6 to 14.3 meters (41 to 47 feet) and a body mass of 13.2 to 23 short tons. The lower estimates for Spinosaurus would imply that the animal was shorter and lighter than some other large theropods like Carcharodontosaurus. Yet there were criticisms for the choice of theropods to compare with and the assumption the skull could be as little as 1.5 meters (4.9 ft) in length.
The debate whether that the Spinosaurus was entirely aquatic, terrestrial or amphibious, switched between both habitats is to this day an active subject of debate. The first thesis about the Spinosaurus, debuts that this theropod was likely a semi aquatic animal. This conclusion has been established by the 2014 fossil discoveries that gave Spinosaurus highly differentiated anatomical features , this conclusion has been bolstered by recent discovery as a highly elongated and dense tail, that might, potentially; helped animal to swim against the current of the Rivers. Studies of the tail, specimens recovered and analyzed by Ibrahim, Pierce, Lauder, and Sereno, in 2018 indicate that Spinosaurus had a keeled tail that was well adapted to propelling the animal through water.
The second consensus that Spinosaurus was likely a terrestrial theropod arises from conducted research that refutes the semi-aquatic thesis for Spinosaurus, such as; a 2018 research, done by paleobiologist Donald Henderson, the research has studying the buoyancy in lungs of crocodilians and comparing it to the lung placement in Spinosaurus, it was discovered that Spinosaurus could not sink or dive below the water surface. It was also capable of keeping its entire head above the water surface while floating, much like other non-aquatic theropods. Furthermore, the study found that Spinosaurus had to continually paddle its hind legs to prevent itself from tipping over onto its side, something that no known extant semi-aquatic animal species do not need to perform. The research conducted that Spinosaurus probably did not hunt completely submerged in water as previously hypothesized, but instead would have spent majority of its life on land or around water  however; these studies of the tail vertebrae of Spinosaurus refute Henderson's proposal that Spinosaurus mainly inhabited areas of land near and in shallow water and was too buoyant to submerge.
The elongated neural spines, which run to the end of the tail on both dorsal and ventral sides, indicate that Spinosaurus was able to swim in a similar manner to modern crocodilians. Through experimentation by Lauder and Pierce, the tail of Spinosaurus was found to have eight times as much forward thrust as the tails of terrestrial theropods like Coelophysis and Allosaurus, as well as being twice as efficient at achieving forward thrust. This discovery indicates that Spinosaurus may have had a lifestyle comparable to modern alligators and crocodiles, that this animal might have capable of remaining in water for long periods of time while hunting.  Additionally; there is also the research conducted at 2010, the scientists directly looked to the oxygen isotope ratios of spinosaurid bones, by comparing Isotope ratios from teeth from Baryonyx, Irritator, Siamosaurus, and Spinosaurus were compared with isotopic compositions from contemporaneous theropods, turtles, and crocodilians. The study found that, among theropods, spinosaurid isotope ratios were closer to those of turtles and crocodilians. However; Siamosaurus specimens tended to have the largest difference from the ratios of other theropods. Spinosaurus tended to have the least difference, this strongly suggests that the different species of Spinosaurids have had differentiated preferences for their habitats. Spinosaurus specimens show similar isotope ratios to other terrestrial theropods. This meant different species of spinosaurids have had differentiated habitat preferences and there are indeed terrestrial Spinosaurus populations or specimens. 
A more recent study or analysis also indicated that the degree of aquatic habitation speculations attributed to Spinosaurus is not consistent, or valid, as well as the features attributed to this theropod indicate a more terrestrial lifestyle akin to wading avians such as the skua, pelicans, shoebills, giant petrels, storks or herons; instead of hyper specialized aquatic to semi aquatic species like dolphins and gharials. 
Diet and feeding
Its unclear that the Spinosaurus was whether a highly specialized piscivore (obligate fish eater) or a generalist carnivore. All known evidence for Spinosaurus dietary preferences, directly comes from the relative spinosauridae species, for example: Baryonyx had shown clear indication for generalist behavior, as one specimen's fossilized rib cage has been found to contain prehistoric species of fish, as well as the remains of a sub-adult Iguanodon, the iberian Baryonyx specimens have also found with direct association to Iguanodons; more examples include another spinosaurid, a more closer relative to Spinosaurus, the Irritator has been found, that either attacked, or ate a large pterosaur  and has been suspected to be the dominant predatory theropod of its environment.  Additionally, there has been the discovery of another spinosaurid, a south Asian spinosaurinae known as Siamosaurus, has been directly consumed sauropods, it's uncertain that if this event was a scavenging situation or a true hunting.
Dal Sasso and colleagues in 2009 reported results of X-ray computed tomography of the MSNM V4047 snout. As the foramina on the outside all communicated with a space on the inside of the snout, the authors had speculated that Spinosaurus had pressure receptors inside its snout used at the surface of the water to detect swimming prey species withaout seeing them. Although this theory remains on speculation with no further publication.
A study in 2013 by Andrew R. Cuff and Emily J. Rayfield did concluded that bio-mechanical data suggests that Spinosaurus was not an obligate piscivore and that its diet was more closely associated with each individual's size. The characteristic rostral morphology of Spinosaurus allowed its jaws to resist bending in the vertical direction, but its jaws were poorly adapted with respect to resisting lateral bending compared to other members of this group baryonychidae like Baryonyx and modern alligators, thus theorizing Spinosaurus could probably preyed more regularly on aquatic prey than it did on terrestrial animals although it is indeed considered predators of the former, too.
Based on the direct paleontological fossil discoveries that Spinosaurus could be a generalist predator that hunted variety of prey item, like aquatic animals such as massive, multi-ton fish species; such as Mawsonia and Onchopristis, the inhabitant crocodylimorphs, as well as the terrestrial animals, as pterosaurs, such as Alanqa, Anhanguera as well as, small to medium sized dinosaurs, such as Ouranosaurus. It is also possible that the Spinosaurus could be a scavenger, as well as a predator; similiar to modern carnivores.
Function of sail
It is uncertain of the function of this dinosaur's sail or hump, scientists have proposed several different hypotheses including display, and heat regulation. The prominent featuer the sail was could've made the animal seem even larger than it was, intimidating other animals. <nowiki>
The structure may have been used for thermoregulation, if the structure contained abundant blood vessels, the animal could have used the sail's large surface area to absorb heat, but this would imply that the animal was only partly warm-blooded at best and lived in climates where night-time temperatures were cool or low and the sky usually not cloudy. It is also quite possible that it could've used it's sail to radiate excess heat from the body, rather than to collect it. Large animals due to the relatively small ratio of surface area of their body compared to the overall volume (Haldane's principle), face far greater problems of dissipating excess heat at higher temperatures, than gaining it at lower. The sails of large dinosaurs added considerably to the skin area of their bodies, but with very minimum increase of volume. In addition, if the sail was turned away from the sun, or positioned at about a 90 degree angle towards a cooling wind, the animal would quite effectively cool itself in the warm climate of Cretaceous Africa. Nevertheless, Bailey (1997) was of the opinion that a sail could have absorbed more heat than it woul have radiated. And Bailey proposed instead that Spinosaurus and other dinosaurs with long neural spines had fatty humps on their backs for energy insulation, storage, and shielding from heat. It is possible that the sail of Spinosaurus was used for courtship, in a way similar to a peacock's tail. Stromer speculated that the size of the neural spines may have differed between males and females.
Gimsa and colleagues (2015) propose that the dorsal sail of Spinosaurus would be analogous to the dorsal fins of sailfish and served a hydrodynamic purpose. Gimsa and others pointed out that the more basal spinosaurids with longer legs round or crescent-shaped dorsal sails, whereas in Spinosaurus, the dorsal neural spines form a shape that was roughly rectangular, similar in shape to the dorsal fins of sailfish. They thus argue that Spinosaurus used its dorsal neural sail in the same manner as sailfish, and that it also employed its long narrow tail to stun prey like a modern thresher shark. The sail might have possibly reduced yaw rotation by counteracting the lateral force in the direction opposite to the slash as suggested by Gimsa and colleagues (2015). Gimsa and colleagues specifically wrote:
"Spinosaurus anatomy exhibits another feature that may have a modern analogy: its long tail resembled that of the thresher shark, employed to slap the water to herd and stun shoals of fish before devouring them (Oliver and colleagues, 2013). The strategies that sailfish and thresher sharks employ against shoaling fish are more effective when the shoal is first concentrated into a ‘bait ball’ (Helfman, Collette & Facey, 1997; Oliver and colleagues, 2013; Domenici and colleagues, 2014). Since this is difficult for individual predators to achieve, they cooperate in this effort. When herding a shoal of fish or squid, sailfish also raise their sails to make themselves appear larger. When they slash or wipe their bills through shoaling fish by turning their heads, their dorsal sail and fins are outstretched to stabilize their bodies hydrodynamically (Lauder & Drucker, 2004). Domenici and colleagues (2014) postulate that these fin extensions enhance the accuracy of tapping and slashing. The sail can reduce yaw rotation by counteracting the lateral force in the direction opposite to the slash. This means that prey is less likely to recognize the massive trunk as being part of an approaching predator (Marras and colleagues, 2015; Webb & Weihs 2015)".
Shape of sail
The sail of Spinosaurus isn't complete in any specimen, they're all partial and incomplete. The new reconstructions of Spinosaurus by Ibraham in 2014 and 2020 reconstruct the sail as roughly square, with a light dip roughly in the middle of the sail. Because the sail of the FSAC-KK 11888 is not very well complete, with only one complete anterior neural spine, and the other 5 anterior spines being incomplete, and the posterior part of the FSAC-KK 11888 sail is unknown. The sail could have been round or have a big notch in the back somewhere, which Scott Hartman made a a speculative skeletal proposing this.
▪NMC 41852/NMC 42852 humerus : Potentially, The Largest Spinosaurinae & Spinosuridae specimen known. Cau et. al. compared it to a Limaysaurus humerus and claimed that it was a rebbachisaur, however later determined that it doesn't match rebbachisaur humeri. Ibrahim et al. (2014) supports a spinosaur affinity 
▪MSNM V4047 : a very large specimen that has been recovered from the Kem Kem fossil beds, estimated to be 15 - 16m long and is currently in the Milano Natural History Museum. Described by Dal Sasso and colleagues in 2005, consists of a snout (premaxillae, partial maxillae, and partial nasals) 98.8 centimeters (38.9 in).
▪NHMUK R 16421 : another, potentially even larger specimen
▪FSAC-KK-11888 : a partial, fragmentary subadult recovered from the Kem Kem beds of North Africa, and described by Ibrahim and colleagues (2014) and designated as the neotype specimen (although Evers and colleagues 2015 reject the neotype designation for FSAC-KK-11888).
▪MSNM V6894 : a potential juvenile
▪BSP 1912 VIII 19: The Holotype specimen known from a left dentary, partial sail, vertebrae, and ribs. Likely a subadult, estimated to be 12 meters long 
▪MNHN SAM 124: Housed at the Muséum National d'Histoire Naturelle, is a upper snout which consists of partial premaxillae, partial maxillae, vomers, and a dentary fragment. Was described by Taquet and Russell in 1998, the specimen is 13.4 to 13.6 centimeters (5.3–5.4 in) in width, yet no length was stated.
The environment inhabited by Spinosaurus is only partially understood, and covers a great deal of what is now northern Africa, from Morocco, Libya, through the Tunisia, and Egypt. The region of Africa Spinosaurus is preserved in dates from 112 to 93.5 million years ago, although a potential specimen has been found in Campanian deposits. In 1996 a study concluded from Moroccan fossils that Deltadromeus, Carcharodontosaurus, and Spinosaurus "ranged across north Africa during the late Cretaceous (Cenomanian)." Those Spinosaurus that lived in the Bahariya Formation of what is now Egypt may have contended with shoreline conditions on channels, and tidal flats and living in mangrove forests alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Aegyptosaurus and Paralititan, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs. Spinosaurus may have resorted to hunting pterosaurs in the dry season. This situation also resembles the Late Jurassic Morrison Formation of North America, which boasts up to five theropod genera over 1.1 short tons in weight, as well as several smaller genera (Henderson, 1998; Holtz and colleagues, 2004). The differences in the body and head shapes in the lareg North African theropods may have been enough to allow niche partitioning, as seen in the many different predator species found today in the African savanna (Farlow & Pianka, 2002).
In the Media
- Spinosaurus has become an iconic dinosaur and its fame started with the film, Jurassic Park III, the first Jurassic Park film not based on a Michael Crichton book. Spinosaurus was portrayed as the main "villain" that caused destruction in its path. In an infamous scene, this Spinosaurus was seen fighting a Tyrannosaurus rex and defeating it. A Spinosaurus fossil Skeleton was seen in Jurassic World where it was destroyed by the Tyrannosaurus Rexy during the Isla Nublar Incident of 2015. It is also one of the dinosaurs included in the Holoscape of Innovation Center, though it is unknown if Spinosaurus actually lives in Jurassic World. Spinosaurus also apparently into cruelty after the Isla Nublar Incident of 2015 before Jurassic World: Fallen Kingdom, on Isla Nublar, though it's unknown if there were any surviving populations left. However, it was planned to be in Jurassic World: Fallen Kingdom has a rematch with the T. rex before being cut from the film entirely. Spinosaurus also appears in most of the Jurassic Park expanded the universe, including games and toy lines.
- A Spinosaurus nicknamed Spiny is one of the main dinosaurs in Dinosaur King, but the depiction of the dinosaur is now considered to be outdated.
- Spinosaurus also appears in many video games such as Jurrasic Park: Operation Genesis, Zoo Tycoon, Carnivores 2, and much more. It is also popular as a player made an animal in "Zoo Tycoon 2".
- Spinosaurus appears in the video game Carnivores 2, with inaccurate anatomy because in the epoch there was little information about this dinosaur.
- Spinosaurus appears in series 4 of Primeval and is shown living in the same place as a Raptor (Dromaeosaur). Another one appears in Series 5.
- Spinosaurus is also in the Discovery Channel's Monsters Resurrected, portrayed as the "Biggest Killer Dino", where it was inaccurately shown to be the super top predator on land. It was seen lifting up and consuming a Rugops whole, kill a Carcharodontosaurus with a single slash of its claws, and slice up the sides of Sarcosuchus. But in the end, it was brought down by a pack of 5 Rugops. The portrayal was noticeably over-powered compared to the real dinosaur.
- Spinosaurus appears in the TV show, Dino Dan, Dino Dan: Trek’s Adventures & Dino Dana as a Popular Character.
- A Spinosaurus, nicknamed "Spike", makes an appearance in the video game Jurassic: The Hunted appears as a boss.
- Spinosaurus appears in National Geographic's Bizarre Dinosaurs, where its sail is talked about. The same Spinosaurus model was briefly seen in another National Geographic Documentary Dinomorphosis.
- Spinosaurus appears in the Japanese animated film Doraemon: Nobita's Dinosaur 2006, where it is the abused pet of an evil time-traveling dinosaur poacher. Also, near the climax, Spinosaurus faces off with Tyrannosaurus only to be defeated.
- Spinosaurus appears in the first episode of BBC's Planet Dinosaur as a fish hunter and during the drought shown to hunt land animals if there are no aquatic animals to eat (no animal eats one thing being an opportunist spinosaurus would likely eat whatever it could), At one of the remaining pools a Sarcosuchus awakens from its hibernation & warded off the Spinosaurus and then resumed hibernation. It later competes against a Carcharodontosaurus for an Ouranosaurus carcass and defeats it in battle with its claws. The same Spinosaurus model was seen in two other Documentaries PBS's Nova National Geographic Special Documentary Bigger Then T.REX & Top 10 Biggest Beasts Ever from Nat. Geo. Wild AKA World's Biggest Beasts from The Smithsonian Channel. Only it was two documentaries.
- It also is a playable character in Primal Carnage.
- Spinosaurus also appears in the 12th episode of The Land Before Time but is inaccurately shown with only two fingers. It was also a minor antagonist in the film.
- A Spinosaurus makes a brief appearance in the Asylum film Age of Dinosaurs where it was running around the city with the rest of the escaped Dinosaurs & somehow is able to climb on top of a tall building.
- Spinosaurus appears in the game Jurassic World: Evolution. It is based on the Jurassic Park III variant.
- In Fossil Fighters series, Spinosaurus is a playable vivosaur.
- Spinosaurus was the main character in Ricardo Delgado's Age of Reptiles: Ancient Egyptians mini-series.
- The Dinobot Scorn of Transformers: Age of Extinction, the Decepticon Undermine and his Autobot copy Repugnus of Transformers: Cybertron all turn into a mechanical version of Spinosaurus.
- The spinosaurus appears in ARK: Survival Evolved as one of the tameable creatures.
- The Spinosaurus appears in the game Parkasaurus.
- Spinosaurus appears in the ROBLOX game "Era of Terror: Remastered", like the other dinosaurs in the game, it starts off as a juvenile then grows into an adult, taking about 40 real-life minutes to complete a growth stage.
- Spinosaurus does appear in the game Jurassic World: Alive as it does in Jurassic Park 3.
- Spinosaurus appears in the game Jurassic World: The Game.
- Spinosaurus made an appearance in the Roblox game called "Dinosaur Simulator."
- It also makes an appearance in the Dora episode, Dora & Diego in the Time of Dinosaurs. It is inaccurately depicted wiggling its spine, but this is not true, since it could kill the dinosaur in actuality.