Lambeosaurinae
Graphical live reconstruction of Lambeosaurus
- Asia
- North America
The Lambeosaurinae is a taxon of hadrosaur. You are on the continents of North America and Asia from the Upper Cretaceous fossil detectable. The most important feature was a comb that out of the premaxillary bone ( premaxilla ) and the nose ( nasal ) was formed. The Lambeosaurinae are the hadrosaur, which are more closely related than Lambeosaurus with Hadrosaurus.
- 2.1 Outer systematics
- 2.2 Evolution and paleobiogeography
- 2.3 Internal systematics
- 3.1 Function of the combs
- 3.2 Habitat and paleoecology 3.2.1 paleoecology
- 4.1 1910-1930
- 4.2 1930-1960
- 4.3 1960-2000
- 4.4 Recent discoveries
Features
Hull and size
The Lambeosaurinae were robust then the Hadrosaurinae. They showed, in contrast to their counterparts in high spinous processes; the back and the tail increased significantly. Up to Olorotitan with 18 cervical vertebrae, the Lambeosaurinae reported as any other hadrosaur up to 15 cervical vertebrae. Is also a feature that the spoke ( radius ) is longer than the upper arm bone (humerus ) was.
The Lambeosaurinae were compared to the Hadrosaurinae relatively large animals. Most genera were 9 to 10 m long. Charonosaurus is on a length of 13 m, Lambeosaurus other hand, is estimated at a size of 15 to 16 m, thus would Lambeosaurus arguably the greatest Lambeosaurinae; when compared becoming the largest Hadrosaurinae, Shantungosaurus, about 14 m long. The oldest known representatives, Nipponosaurus, was a rather small Lambeosaurinae with 8 m.
The main feature of Lambeosaurinae is from Zwischenkieferbein ( premaxilla ) and nose ( nasal ) formed bone crest. The directed mostly to the back ridge varies in the form of bone- cone-like (eg Parasaurolophus ) to beilförmig, patten or like a helmet (eg Corythosaurus ). In the genus Tsintaosaurus the comb shape is controversial, but is often interpreted as a unicorn -like. However, may also be scarce crest. The size dimorphism suggests in a way that males and females had two different combs. The combs were crossed tubes, which sounds could be produced. In the combs were four tubes, two went up, two down; the air to pass through to the whole tubes.
As with all all Hadrosauriern the snout was wide, but narrower than in the Hadrosaurinae. In Lambeosaurus a pointing towards the muzzle outgrowth of the zygomatic bone ( Jugale ) had a triangular shape.
Systematics and evolution
Outer systematics
The Lambeosaurinae is compared with the Hadrosaurinae. The main difference is that the Hadrosaurinae does not have a comb. Both taxa in turn form the taxon Euhadrosauria. Cladogram loud Vecchia:
Telmatosaurus
Hadrosaurinae
Lambeosaurinae
Evolution and paleobiogeography
In the 1980s, the hadrosaur -like skull of the genus Ouranosaurus sparked a discussion. According to Philippe Taquet the skull of Ouranosaurus resembled the Hadrosauriern so much that he could be an ancestor of Hadrosauridae, and thus an ancestor of Lambeosaurinae. Jack Horner said 1990 Ouranosaurus have similar features as the Skull Lambeosaurinae; thus Ouranosaurus and Lambeosaurinae were summarized as Lambeosauria. The Hadrosaurinae other hand, are more closely related to Iguanodon. If this theory is correct, then the hadrosaur not form a monophyletic clade more, but the Lambeosaurinae and Hadrosaurinae evolved from separate ancestors and other times. This theory is not proved.
The origin of the Lambeosaurinae itself was probably Asia. There the genera Aralosaurus and Jaxartosaurus seceded. Also wandered a part of a population toward China; there arose the genus Tsintaosaurus. The other part of the population migrated across the Bering Strait to North America a. There split the Parasaurolophini from the other Lambeosaurinae, the Corythosaurini, from and formed by adaptation to nature the peg- like ridges. Since the Lambeosaurinae have been found more in the north than in the south of North America, this also speaks for this development. The North American Lambeosaurinae probably also migrated back to Asia. A good example of this theory are Charonosaurus and Parasaurolophus: Both have snorkel -like ridges on. Since Charonosaurus is geologically younger than Parasaurolophus, Parasaurolophus could have migrated to Asia. The Lambeosaurinae died in North America before the end of the Cretaceous, in Asia they died with all other non-avian dinosaurs at the end of the Cretaceous period around 66 million years ago from.
Inside systematics
The Lambeosaurinae can generally be divided into two tribes: In the Parasaurolophini, with the snorkel -like ridges, and in the Corythosaurini with the "round" combing, which also includes the genus Lambeosaurus heard. The basal Lambeosaurinae are among other Tsintaosaurus and Olorotitan.
Jaxartosaurus
Pararhabdodon
Tsintaosaurus
Olorotitan
Parasaurolophus
Charonosaurus
Nipponosaurus
Sahaliyania
Corythosaurus
Lambeosaurus
Paleobiology
Function of the combs
The function (s ) of the crests of the Lambeosaurier is controversial. Previously, the hadrosaur were interpreted as amphibious animals; the comb, might have been a kind of snorkel especially in Parasaurolophus. Other suggestions are that the comb was used as a salt gland or enhanced sense of smell. It is widely assumed that the combs were colorful and served in the courtship. The cavities were connected to the trachea and to the nose. This sounds to be generated.
Habitat and paleoecology
Previously it was assumed that the Lambeosaurinae like other hadrosaurs lived amphibious. Richard Deckert represented the genus Corythosaurus in the water with horizontal body on land, however, Deckert reconstructed him standing on two legs. The describer Barnum Brown graduated from the high, laterally flattened tail on a floating life. This theory persisted for decades. Further support of this theory the amphibious lifestyle was the snorkel -like crest of Parasaurolophus.
Today we know that the Lambeosaurinae were terrestrial, so land-living animals. In North America, the landscape in Alberta was crossed in the north of rivers and marshy meadows and there was one from the Western Interior Seaway marine -influenced climate in New Mexico in the south of North America was due to the retraction of the Western Interior Seaways a floodplain.
In Asia, there were both desert and forest. Among other things, there were also some lakes.
Paleoecology
In the Dinosaur Park Formation in North America, were found in the Lambeosaurinae, many ceratopsians were found, including Centrosaurus, Styracosaurus and Chasmosaurus, but the North American Lambeosaurinae shared their habitat with both the Hadrosaurinae Prosaurolophus and Gryposaurus, the Ankylosauriden Edmontonia and Euoplocephalus, and the Tyrannosauroiden Gorgosaurus. In the Horseshoe Canyon Formation, also North America, the Lambeosaurinae shared the habitat with the Edmontosaurus regalis Hadrosaurinae and Saurolophus osborni, the ceratopsians with the types Pachyrhinosaurus canadensis, Anchiceratops ornatus, Arrhinoceratops brachyops and Eotriceratops xerinsularis. Rarely Ankylar, including Euoplocephalus tutus and Edmontonia longiceps or Pachycephalosaurier as Stegoceras were edmontonense. Also a ornithischians is the Ornithopod Parksosaurus warrenae. The theropods were very common with the Ornithomimiden as Dromiceiomimus brevitertius, Ornithomimus edmontonicus and Struthiomimus altus. The Spitzenprädator was the Albertosaurus sarcophagus Tyrannosauride. Smaller robbers were Ricardoestesia isosceles, the Caenagnathiden Chirostenotes pergracilis, the Troodon formosus and the Troodontide Dromaeosauriden Atrociraptor marshalli, Dromaeosaurus sp. and Saurornitholestes sp.
In Asia, the Lambeosaurinae shared the habitat with the Hadrosaurine Kerberosaurus, the Protoceratopsiden Protoceratops, some Pachycephalosaurier, the Ankylar Saichania the habitat, theropods were represented by the genera Tarbosaurus and Velociraptor.
Diet
All Lambeosaurinae were herbivores. The advanced pine milled chewing allowed. The ridges, formed tooth batteries, in which several hundred teeth were arranged; there were always used several teeth. Worn teeth were continually replaced. The plants were picked off first with the beak and then kept in cheek -like mouthparts. Paleontologist Robert Bakker said the Lambeosaurinae have narrower snouts than the Hadrosaurinae. Bakker theorized that the Lambeosaurinen hadrosaur were wählerischere herbivores.
Discovery and exploration history
1910-1930
The first known Lambeosaurinae was the Hypacrosaurus described by Barnum Brown in 1913. He was originally known by ribs, vertebrae, shoulder and pelvic girdle and bones of limbs. Brown, however, was the giant growth, and said this hadrosaur an " upright height" of nearly the Tyrannosaurus, calling it " almost largest lizard". The shape of the skull was known in 1924 by a description of a second copy. In 1914, Brown described Corythosaurus; he was named after a remarkable find at Steve Ville at Red Deer River, Alberta, 1912. Completely preserved except for a portion of the front legs and the tail. Significantly, among other things, that the fossils of Corythosaurus are very well preserved, they show the outlines of the soft tissues of the whole animal, even the skin. However, Brown was aware of parallel, vertical folds; they were clearly visible in the shoulder and in the fuselage. Brown said there were " loose skin wrinkles" that need to be visible in the living animal. According to Brown, the Corythosaurus Fossil have shown next to large eddy sequels vertical skin furrows. Richard Deckert reconstructed Corythosaurus for Browns items with a folded skin surface. As Deckert Corythosaurus upright reconstructed and floating ashore with two legs, is held the theory that hadrosaurs were amphibious, in the early 20th century.
When the University of Toronto made an expedition to Alberta, was also discovered the genus Parasaurolophus at the Red Deer River, 1920. The specimen is the holotype with the copy number ROM 768 It consists of a partial skeleton with skull, but lacks the leg bone below the knee joints and the majority of the tail. The animal was described in 1922 by William Parks and Parasaurolophus walkeri called it. However, in 1917 some Parasaurolophus fossils were discovered, but only in 1924 by Gilmore as Lambeosaurus sp. described. Due to the shape of the ridge, it was assumed that it was used as a snorkel, thus supporting the theory that hadrosaurs were amphibious animals. Park believed Parasaurolophus was a close allied of Saurolophus, so the name " almost Saurolophus ". However remarked parks that the snout of the animal resembled by Corythosaurus and suspected a relationship between the two genera, which also was confirmed. Parks assumption that the bone plug is connected to a skin collar with his back, but was not confirmed, the painter Charles Knight but recorded Parasaurolophus by Parks conjecture.
William Parks in 1922 the new genus Lambeosaurus. The fossils were in the Judith River Group in Dinosaur Provincial Park, Alberta. It was almost 20 relatively well-preserved skull, sometimes with associated skeletons. There are both adult ( ARISING ) and juveniles found. In the El Gallo Formation in the Mexican state of Baja California Norte another partial skeleton of Lambeosaurus was exposed.
1930-1960
1931 A new species of the genus Parasaurolophus was discovered: Parasaurolophus tubicen. The species was described by Carl Wiman, however, already discovered in 1921. The species name tubicen comes from the Latin and means " trumpeter ".
On the island of Sakhalin, a new species was discovered in 1936, which is known as Nipponosaurus sachalinensis. It was described by Japanese paleontologists Nagao. The name means " lizard from Japan" as the island once belonged to Japan, today it is ruled by Russia.
The paleontologist Anatoly Nikolayevich Ryabinin described, according to sources in 1937 or 1939, the new, little-known type Jaxartosaurus aralensis.
In the 1940s, no further Lambeosaurinae were discovered only in 1958, described the Chinese paleontologist Yang Zhongjian the new genus Tsintaosaurus. Tsintaosaurus is named after the city of Tsingtao ( Qingdao). The only way is Tsintaosaurus spinorhinus; the species name spinorhinus means "thorn nose ". He is the first known Lambeosaurinae wearing a unicorn -like crest.
1960-2000
Anatoly Konstantinovich Rozhdestvensky 1968 had the kind Aralosaurus tuberiferous described. Were discovered the fossils of the genus in Kazakhstan in the Beleutinsk formation near the Aral Sea. He is known by a partially preserved skull, some vertebrae, limb bones and some teeth.
1993 was described Pararhabdodon isonensis of Casanova - Cladellas, Santafe - Llopis and Isidoro Llorens. He was a possible related the Tsintaosaurus. A possible synonym is Koutalisaurus.
Recent discoveries
In 2000, a new species has been described, the Parasaurolophus looked like: Charonosaurus jiayinensis. He was found and excavated in the Yuliangze lineup in the years 1916/1917. The holotype is a fragmentary skull, which was described in 2000 by Pascal Godefroit, Zan Shuqin and Jin Liyong as Charonosaurus.
In 2003, the Asian Olorotitan described. It was discovered in the Udurchukan formation (the lower part of the Tsagayan Group) 1991.
More discoveries from the years 2006 to 2010 were Koutalisaurus kohlerorum, Nanningosaurus dashiensis, Velafrons coahuilensis, Sahaliyania elunchunorum, Arenysaurus ardevoli, Angulomastacator daviesi and Blasisaurus canudoi.
In popular culture
Although most Lambeosaurinae are quite unknown, there are some types that are common in documentaries, feature films, etc.. The most famous dinosaur of this subfamily is Parasaurolophus. It comes in the feature films The Land Before Time (although actually a Saurolophus ), in " Le Sacre du Printemps " from Disney's "Fantasia", in all three "Jurassic Park " movies and Disney's " Dinosaur " before. Even as a toy of the Parasaurolophus is popular, as it is produced, for example, in the company Schleich.
The genus Corythosaurus is found in many popular science books. Other, less well-known genera include Lambeosaurus and Tsintaosaurus.