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''Lurdusaurus'' ("heavy lizard") is a
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of massive and unusually shaped
iguanodont Iguanodontia (the iguanodonts) is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous. Some members include ''Camptosaurus'', ''Dryosaurus'', ''Iguanodon'', '' Tenontosaurus'', and the hadrosaurids or "duck-bil ...
dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...
from the
Elrhaz Formation The Elrhaz Formation is a geological formation in Niger, central Africa. Its strata date back to the Early Cretaceous, about 125 to 112 million years ago. Dinosaur remains are among the fossils that have been recovered from the formation, alongsi ...
in Niger. It contains one species, ''L. arenatus''. The formation dates to the Early Cretaceous, roughly 112 million years ago. ''Lurdusaurus'' has a highly atypical body plan for an iguanodont, with a small skull, long neck, rotund torso, and powerful forelimbs and claws, somewhat reminiscent of a ground sloth. Its
metacarpal In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones ar ...
s (wrist bones) are fused and reinforced into a large block, and the thumb spike is remarkably enormous. These would have allowed the hand to have functioned almost like a ball-and-chain flail. ''Lurdusaurus'' is estimated to have been long and high when on all-fours, but its stomach would have been only off the ground. It may have weighed , conspicuously heavy for an iguanodontid this size. Paleontologist Thomas R. Holtz Jr. speculated ''Lurdusaurus'' may have behaved much like a
hippo The hippopotamus ( ; : hippopotamuses or hippopotami; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus, or river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extant ...
. It lived in a forested, riverine environment alongside the iguanodonts '' Ouranosaurus'' and ''
Valdosaurus ''Valdosaurus'' ("Weald Lizard") is a genus of bipedal herbivorous iguanodont ornithopod dinosaur found on the Isle of Wight and elsewhere in England, Spain and possibly also Romania. It lived during the Early Cretaceous. Discovery and naming ...
'', the sauropod ''
Nigersaurus ''Nigersaurus'' is a genus of rebbachisaurid sauropod dinosaur that lived during the middle Cretaceous period, about 115 to 105 million years ago. It was discovered in the Elrhaz Formation in an area called Gadoufaoua, in Niger. Fossils of th ...
'', an undescribed
titanosaurid Lithostrotia is a clade of derived titanosaur sauropods that lived during the Early Cretaceous and Late Cretaceous. The group was defined by Upchurch ''et al.'' in 2004 as the most recent common ancestor of '' Malawisaurus'' and '' Saltasaurus'' ...
, the spinosaurid '' Suchomimus'', the
carcharodontosaurid Carcharodontosauridae (carcharodontosaurids; from the Greek καρχαροδοντόσαυρος, ''carcharodontósauros'': "shark-toothed lizards") is a group of carnivorous theropod dinosaurs. In 1931, Ernst Stromer named Carcharodontosauridae ...
''
Eocarcharia ''Eocarcharia'' (meaning "dawn shark") is a genus of carcharodontosaurid theropod dinosaur from the Early Cretaceous Elrhaz Formation that lived in the Sahara 112 million years ago, in what today is the country of Niger. It was discovered in 2 ...
'', the
abelisaurid Abelisauridae (meaning "Abel's lizards") is a family (or clade) of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are foun ...
''
Kryptops ''Kryptops'' is a genus of abelisaurid theropod dinosaur from the Early Cretaceous of Niger. It is known from a partial skeleton found at the Gadoufaoua locality in the western Ténéré Desert, in rocks of the Aptian-Albian age Elrhaz Formation ...
'', and an undescribed noasaurid. The site also yielded several
crocodylomorph Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. During Mesozoic and early Cenozoic times, cro ...
species and a
pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 ...
.


Discovery

In 1965,
Philippe Taquet Philippe Taquet (b. April 25, 1940 Saint-Quentin, Aisne) is a French paleontologist who specializes in dinosaur systematics of finds primarily in northern Africa. He is a member of the French Academy of Sciences since November 30, 2004, president ...
discovered the
holotype specimen A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
at the Gadoufaoua site of the
Elrhaz Formation The Elrhaz Formation is a geological formation in Niger, central Africa. Its strata date back to the Early Cretaceous, about 125 to 112 million years ago. Dinosaur remains are among the fossils that have been recovered from the formation, alongsi ...
, in the Tenere desert of Niger. It consists of a nearly complete adult
iguanodont Iguanodontia (the iguanodonts) is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous. Some members include ''Camptosaurus'', ''Dryosaurus'', ''Iguanodon'', '' Tenontosaurus'', and the hadrosaurids or "duck-bil ...
skeleton with a fragmentary skull belonging to single individual, which was given the catalogue number MNHN GDF 1700. He noted it had rather massive proportions, and in 1976 noted it should probably be classified into a new genus while briefly describing the material. Paleontologist Souad Chabli described the remains in 1988 for her PhD thesis, under the direction of Taquet. She named it "''Gravisaurus tenerensis''". However, her dissertation was never published. In 1999, Turquet and American paleontologist Dale Russell published the first formal description, naming it ''Lurdusaurus arenatus''. The generic name comes from
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
''lurdus'' "heavy" and
Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...
''sauros'' "lizard", in reference to the enormous weight of the fossils. The specific name ''arenatus'' is Latin for "sandy" because it was found in a desert. They also referred a
dentary In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...
fragment, MNHN GDF 43G, and a right
coracoid A coracoid (from Greek κόραξ, ''koraks'', raven) is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is prese ...
, GDF 381, to the species.


Description

The tip of the snout may have been about wide, and expanded back to . That is, like other iguanodonts, it did not have a duck-like bill. No teeth were preserved, but MNHN GDF 43G preserves the tooth sockets for 10 tooth rows within . The
quadrate bone The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids (reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms upper pa ...
at the base of the skull has an exceptionally low stature at , in contrast to in ''
Mantellisaurus ''Mantellisaurus'' is a genus of iguanodontian dinosaur that lived in the Barremian and early Aptian ages of the Early Cretaceous Period of Europe. Its remains are known from Belgium ( Bernissart), England, Spain and Germany. The type and only ...
'' and in ''
Iguanodon ''Iguanodon'' ( ; meaning ' iguana-tooth'), named in 1825, is a genus of iguanodontian dinosaur. While many species have been classified in the genus ''Iguanodon'', dating from the late Jurassic Period to the early Cretaceous Period of Asia, ...
''. Based on the ratio between the length of the snout and the length of the rest of the skull in iguanodonts, the total length of the holotype's skull may have been in life. ''Lurdusaurus'' may have had 12 to 14 neck vertebrae. Therefore, the maximum length of the neck is . The neck vertebrae are about the same size as the
dorsal vertebrae In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae and they are intermediate in size between the cervical ...
(the torso, before the sacrum and pelvis), whereas those of European iguanodonts 85–90% the size of the dorsals. Because ''Iguanodon'' has 28 presacral vertebrae, ''Lurdusaurus'' potentially had at least 14 dorsals. This would make the neck proportionally quite long, as long as the dorsal series. Compared to European iguanodonts, the dorsal centra are proportionally larger and have shorter neural spines (which project straight up from the centrum) and less steep transverse processes (which project up obliquely). Like all derived iguanodonts, the
sternum The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sha ...
is hatchet-shaped, with a rod-shaped projection caudolaterally (tailwards towards the side). The sacrum, based on the scars on the ilium begotten from sacral ribs, may have measured . ''Lurdusaurus'' could have had 15 proximal
caudal vertebra The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic ...
(tail vertebrae which bear transverse processes), which would have represented a third of the entire tail series. This would equate to a tail, and a total body length of . It may have been tall at the hips. Based on the length of the ribs, the stomach may have been less than off the ground when standing
quadrupedal Quadrupedalism is a form of locomotion where four limbs are used to bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four limbs is said to be a quadruped (from Latin ''quattuor ...
ly (on all-fours). Based on the circumferences of the limbs – for the humerus and for the
femur The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates wit ...
– Taquet and Russell estimated that the holotype weighed approximately , conspicuously heavy for an
ornithopod Ornithopoda () is a clade of ornithischian dinosaurs, called ornithopods (), that started out as small, bipedal running grazers and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous wo ...
this size. In 2016, however, Gregory S. Paul proposed a significantly lower size estimate of in length and in body mass. The headward dorsal ribs are preserved in their original positions, and show the torso was rather rotund. The diverging wings of the ilia and horizontally-orientated tailward dorsal ribs indicate a flat back about across. The limbs are exceptionally massive and proportionally stout. The forelimbs are 60% the size of the hindlimbs. The
metacarpal In human anatomy, the metacarpal bones or metacarpus form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist, which forms the connection to the forearm. The metacarpal bones ar ...
s in the wrist were fused together into a massive block, which is also exhibited in ''Iguanodon'', ''Ouranosaurus'', and ''
Camptosaurus ''Camptosaurus'' ( ) is a genus of plant-eating, beaked ornithischian dinosaurs of the Late Jurassic period of western North America and possibly also Europe. The name means 'flexible lizard' ( Greek (') meaning 'bent' and (') meaning 'li ...
''. Like ''Camptosaurus'' but unlike derived iguanodonts, the metacarpals (except for the thumb) were short and dumbbell-like as opposed to long and narrow. Compared to ''Camptosaurus'', the
ungual An ungual (from Latin ''unguis'', i.e. ''nail'') is a highly modified distal toe bone which ends in a hoof, claw, or nail. Elephants and ungulates have ungual phalanges, as did the sauropod Sauropoda (), whose members are known as sauropods (; ...
s (claws) are flatter. The hand features a massive thumb spike. The pelvis is proportionally short but powerful, somewhat reminiscent of a ceratopsian pelvis. The femur slightly recurves toward the midline like in ceratopsians, and is flattened anteroposteriorly (from front to back) like in sauropods. The heavily built
fourth trochanter The fourth trochanter is a shared characteristic common to archosaurs. It is a knob-like feature on the posterior-medial side of the middle of the femur shaft that serves as a muscle attachment, mainly for the '' musculus caudofemoralis longus'' ...
is located on the bottom half of the femur, like ''Iguanodon'' but unlike ''Mantellisaurus'' and '' Ouranosaurus''. The tibia is incredibly short relative to the femur, respectively vs. . The
metatarsal The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the me ...
s were too short to make contact with each other, and there was likely a fleshy pad to support the weight.


Classification

In 1999, Taquet and Russell classified ''Lurdusaurus'' as a derived iguanodont or an intermediate between the iguanodonts and the more derived
hadrosaur Hadrosaurids (), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which incl ...
s, based on the presence of a posterolaterally orientated (towards the back and side) process on the
sternum The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sha ...
, slight tailward expansion of the pubis, a reduced posterior process of the pubis, and opisthocoelus (concave posterior ends) neck vertebrae and front dorsal vertebrae. They preliminarily placed it into the
family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Iguanodontidae Iguanodontidae is a family of iguanodontians belonging to Styracosterna, a derived clade within Ankylopollexia. Characterized by their elongated maxillae, they were herbivorous and typically large in size. This family exhibited locomotive dynam ...
, though conceded there is poor resolution on its higher classification, because the fourth trochanter is almost suspended off the femur like basal iguanodonts, but the neck vertebrae series is long like hadrosaurs. They were unable to satisfactorily explain the evolution of such an unusual body plan. In 2004, British paleontologist David B. Norman placed it outside of Iguanodontidae but still within the clade Styracosterna, which he defined as containing all iguanodonts with a hatchet-like sternum and flattened hand claws. He agreed ''Lurdusaurus'' is a more derived iguanodont. In 2005, Chinese paleontologist You Hai-Lu and colleagues suggested that the newly discovered and massively built '' Lanzhousaurus'' from China was closely related to ''Lurdusaurus'', and the former was basal to the latter. He classified both of them as basal styracosterns. In 2008, American freelance researcher
Gregory S. Paul Gregory Scott Paul (born December 24, 1954) is an American freelance researcher, author and illustrator who works in paleontology, and more recently has examined sociology and theology. He is best known for his work and research on theropod dino ...
argued that because ''Lanzhousaurus'' has a much deeper prepubic process, the two genera are probably not closely allied, though such hypotheses are wholly unverifiable without more complete remains. Paul agreed that ''Lurdusaurus'' is more basal to Iguanodontidae based on its short, broad hands and massive thumb spike, but he noted that the contemporary and more derived hadrosauriform ''Ouranosaurus'' has similar hand morphology. Therefore, ''Lurdusaurus'' could be a basal hadrosauriform, but Paul could not resolve the matter any further until more complete remains are discovered. In 2009, American paleontologist
Peter Galton Peter Malcolm Galton (born 14 March 1942 in London) is a British vertebrate paleontologist who has to date written or co-written about 190 papers in scientific journals or chapters in paleontology textbooks, especially on ornithischian and prosa ...
placed ''Lurdusaurus'' at the base of Styracosterna and closely allied it with the Chinese '' Equijubus''. He classified more derived iguanodonts into the new clade Iguanodontea. In 2012, Taquet agreed with Paul that it falls outside Iguanodontidae, but was also unsure how exactly ''Lurdusaurus'' relates with other iguanodonts. Phylogeny of
Iguanodontia Iguanodontia (the iguanodonts) is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous. Some members include ''Camptosaurus'', ''Dryosaurus'', ''Iguanodon'', '' Tenontosaurus'', and the hadrosaurids or "duck-bil ...
according to
Galton Sir Francis Galton, FRS FRAI (; 16 February 1822 – 17 January 1911), was an English Victorian era polymath: a statistician, sociologist, psychologist, anthropologist, tropical explorer, geographer, inventor, meteorologist, proto- ...
, 2009 (left) and You and colleagues, 2005 (right)


Paleoecology

In 2007, paleontologist Thomas R. Holtz Jr. speculated that "''Lurdusaurus'' may have been the dinosaur equivalent to a
hippo The hippopotamus ( ; : hippopotamuses or hippopotami; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus, or river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extant ...
" as they both share a heavy, stocky body plan. He suggested ''Lurdusaurus'', like the hippo, was a generally slow-moving animal on both land and water, but could reach high speeds when necessary. Generally, iguanodonts are thought to have been predominantly
biped Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' ...
al or facultatively bipedal, and ''Lurdusaurus'', judging by the marked robustness of the limbs, was likely capable of quadrupedal locomotion for an extended period of time. Overall, with its unusual and massive body plan including a small skull, circular chest, powerful and clawed forearms, and flattened femora, ''Lurdusaurus'' may have been reminiscent of a ground sloth. In squatting position, it may have resembled an ankylosaur. Taquet and Russell compared the fortified hand with its massive thumb spike to a ball-and-chain flail, and believed it was primarily used for defense. ''Lurdusaurus'' was recovered from the Elrhaz Formation, and lived alongside the iguanodonts '' Ouranosaurus'' and '' Elrhazosaurus'', the sauropod ''
Nigersaurus ''Nigersaurus'' is a genus of rebbachisaurid sauropod dinosaur that lived during the middle Cretaceous period, about 115 to 105 million years ago. It was discovered in the Elrhaz Formation in an area called Gadoufaoua, in Niger. Fossils of th ...
'', an undescribed
titanosaurid Lithostrotia is a clade of derived titanosaur sauropods that lived during the Early Cretaceous and Late Cretaceous. The group was defined by Upchurch ''et al.'' in 2004 as the most recent common ancestor of '' Malawisaurus'' and '' Saltasaurus'' ...
, the spinosaurid '' Suchomimus,'' the
carcharodontosaurid Carcharodontosauridae (carcharodontosaurids; from the Greek καρχαροδοντόσαυρος, ''carcharodontósauros'': "shark-toothed lizards") is a group of carnivorous theropod dinosaurs. In 1931, Ernst Stromer named Carcharodontosauridae ...
''
Eocarcharia ''Eocarcharia'' (meaning "dawn shark") is a genus of carcharodontosaurid theropod dinosaur from the Early Cretaceous Elrhaz Formation that lived in the Sahara 112 million years ago, in what today is the country of Niger. It was discovered in 2 ...
'', the
abelisaurid Abelisauridae (meaning "Abel's lizards") is a family (or clade) of ceratosaurian theropod dinosaurs. Abelisaurids thrived during the Cretaceous period, on the ancient southern supercontinent of Gondwana, and today their fossil remains are foun ...
''
Kryptops ''Kryptops'' is a genus of abelisaurid theropod dinosaur from the Early Cretaceous of Niger. It is known from a partial skeleton found at the Gadoufaoua locality in the western Ténéré Desert, in rocks of the Aptian-Albian age Elrhaz Formation ...
'', and an undescribed noasaurid. The Gadoufaoua site has also yielded an ornithocheirid
pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 ...
, and the
crocodylomorph Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. During Mesozoic and early Cenozoic times, cro ...
s ''
Anatosuchus ''Anatosuchus'' ("duck crocodile", the name from the Latin ''anas'' ("duck") and the Greek ''souchos'' ("crocodile"), for the broad, duck-like snout) is an extinct genus of notosuchian crocodylomorph discovered in Gadoufaoua, Niger, and described ...
'', ''
Araripesuchus ''Araripesuchus'' is a genus of extinct crocodyliform that existed during the Cretaceous period of the late Mesozoic era some 125 to 66 million years ago. Six species of ''Araripesuchus'' are currently known. They are generally considered to be n ...
'', ''
Stolokrosuchus ''Stolokrosuchus'' is an extinct genus of neosuchian crocodylomorph that lived during the Early Cretaceous. Its fossils, including a skull with a long thin snout and bony knobs on the prefrontal, have been found in Niger. ''Stolokrosuchus'' wa ...
'', and the giant ''
Sarcosuchus ''Sarcosuchus'' (; ) is an extinct genus of crocodyliform and distant relative of living crocodilians that lived during the Early Cretaceous, from the late Hauterivian to the early Albian, 133 to 112 million years ago of what is now Africa and ...
''. It dates to roughly 112 million years ago during the Early Cretaceous at the Aptian
Albian The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/ Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0 ...
boundary. Geologically, it is composed of almost entirely cross-bedded fluvial
sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...
(the sediments were deposited by rivers), intermittently interrupted by migrating sand dunes. The presence of ''Nigersaurus'' suggests widespread forests with soft
understory In forestry and ecology, understory (American English), or understorey (Commonwealth English), also known as underbrush or undergrowth, includes plant life growing beneath the forest canopy without penetrating it to any great extent, but abo ...
vegetation, such as immature
fern A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes exce ...
s or
horsetail ''Equisetum'' (; horsetail, snake grass, puzzlegrass) is the only living genus in Equisetaceae, a family of ferns, which reproduce by spores rather than seeds. ''Equisetum'' is a "living fossil", the only living genus of the entire subclass ...
s.


See also

*''
Koreaceratops ''Koreaceratops'' () is a genus of basal ceratopsian dinosaur discovered in Albian-age Lower Cretaceous rocks of South Korea. Discovery It is based on KIGAM VP 200801, an articulated series of 36 caudal vertebrae associated with ...
'' *''
Liaoningosaurus ''Liaoningosaurus'' is an unusual genus of ankylosaurian dinosaurs from the Early Cretaceous period of China. It contains a single species, ''Liaoningosaurus paradoxus'', and is represented by two fossil specimens collected from the Yixian Form ...
'' *''
Spinosaurus ''Spinosaurus'' (; ) is a genus of spinosaurid dinosaur that lived in what now is North Africa during the Cenomanian to upper Turonian stages of the Late Cretaceous period, about 99 to 93.5 million years ago. The genus was known first f ...
''


References

{{Taxonbar, from=Q548399 Iguanodonts Early Cretaceous dinosaurs of Africa Aptian life Cretaceous Niger Fossils of Niger Fossil taxa described in 1999 Taxa named by Philippe Taquet Taxa named by Dale Russell Ornithischian genera