THE ORNITHOPODAN DINOSAURS

 

Anatosaurus

An-AT-oh-SAW-rus

Duck reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada

Anatosaurus was the classic "duck-billed" dinosaur. It had a low skull, without a crest, and a broad snout area like a duck's beak. It was a large animal, up to 43ft. (13m) long. Anatosaurus is known by many skeletons, and some have been "mummified" so that parts of the skin have been preserved. There were several species of Anatosaurus that lived right through to the end of the Cretaceous period.

 

Brachylophosaurus

BRACK-ee-LOAF-oh-SAW-rus

Short . crested reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada

Brachylophosaurus was one of the most primitive duck-billed dinosaurs, or hadrosaurs. It had a simple crest made from the nasal bones. These ran back between the eyes to form a broad plate. There was a little spike pointing backward. The crest was solid in Brachylopshosaurus, and its exact purpose is hard to determine. It may have been an identification. It may have been an identification signal to let other dinosaurs known what kind of dinosaur it was.

 

Camptosaurus

KAMP-toe-SAW-rus

Bent reptile

Ornithischia: Ornithopoda

Late Jurassic and early Creataceous

Wastern Europe and western USA

Camptosaurus was heavily built up to 23ft (7m) long. It was similar in many respects to iguanodon, Camtosaurus had long powerful hindlegs and much shorter arms. However, it had small hooves on each finger of the heand, which shows that it walked on all fours at least some of the time. About ten spicies of Comptosaurus have been decribed from fiffrent pats of Europe and North America. These all differ by size and proportion, but it shows how widespread this dinosaur was.

 

Claosaurus

CLAY-oh-SAW-rus

Branched reptile

Ornithischia: Ornithopoda

Late Cretaceous

Kansas, USA

Claosaurus was noe of the earliest duck-billed dinosaurs. The duck bills, such as corythosaurus, parasaurolophus and tsintaosaurus, often had fancy crets on top of their heads. Claosaurus hardly had any crest. It was alsoprimitive in features of its legs and feet. Its slim body was only 12ft. (3.5m) or so long.

 

Corythosaurus

Ko-RITH-oh-SAW-rus

Helmet reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada

Corythosaurus is one of the best known of the hadrosaurs (duck-billed dinosaurs). It was a large animal – over 33ft (10m) lnog. The crest on top of the head was high and narrow from side to side. It was from the nostrils on the snout up into the crest and then down again into the mouth. Corythosaurus may have used this complicated breathing-tube system to make loud bellows and honks. There are several species of Corythosaurus which are based on the shape of the crest. The closest relative of Corythosaurus was lambeosaurus.

 

Dryosaurus

DRY-oh-SAW-rus

Oak reptile

Ornithischia: Ornithopoda

Late JurassicWestern USA, Tanzania

Dryosaurs was a relative of hypsilophodon, but much larger: Dryosaurus was 10-13ft. (3-4m) long. It had powerful legs, and strong arms, each with five fingers. Dryousaurus could have run fast on its hing legs. Its tail was stiff and it could have been used for balance. Dryosaurus probably used its hand to gather plants to eat. Its back teeth were sharp and ridget, but the teeth at the front of the jaw were not. Dryosaurus is known from several skletons and skulls from africa and Nort America,which proves that these two parts of the world were joined 140million yearc ago. Dryosaurs lived with the well known ssauropods apatosarus, brachiosaurus and diplodocus, the stegosaurs stegosaurus and kentrosaurus and the meat-eaters allosaurus, coelurus and elaphrosaurus.

 

 

Edmontosaurus

e-MON-oh-SAW-rus

Edmonton reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canadan and Montana USA

Edmontosaurus was a duck-billed dinosaur with a flat head, rather like anatosaurus and shantungosaurus. Edmontosaurus is quite weèè known because several skeletons havee been found. It was one of the largest duck-billed, 43ft (13m) long. The skull was low in front and high in back. There was a wide duck-like beak (as in Antatosaurus) Edmontosaurus had about a thousand strong teeth, and probably fed ao tough plants which neede to be well chewed.

 

 

Fabrosaurus

FAB-roe-SAW-rus

Fabre's reptile

Ornithischia: Ornithopoda

Late Triassic/ early Jurassic

Lesotho, South Africa

Fabrosaurus was an early primitive ornithopod related to scutellosaurus. It was only 40in (1m) long and would not have been able look over a dinner table if it had stood upas straight it could. Fabrosaurus was very lightly built and ran on its hind legs. It had strong arms and hands: The teeth were strong, with frilled or knobbly edges. This shows that Fabrosaurus could use its teeth to chop up vegetation.

 

Geranosaurus

Jer-AN-oh-SAW-rus

Crane reptile

Orinithischia: Ornithopoda

Late Triassic/early Jurassic

South Africa

Geranosaurus was a small ornithopos that was closly related to hieterodontosaurus and lycorhinus. It is only known from parts of its jaws and a few other bones. The jawsshow that it had sharp teeth at the front of the jaw , a pair of fangs behind, and ridged cheek teeth at the back. The front teeth were used to snip off pieces of plants.

 

Hadrosaurus

HAD-roe-SAW-rus

Bulky reptile

Orinthischia: Ornithopoda

Late Cretaceous

New Jersey and New Mexcico, USA, And Alberta, Canada

Hadrosaurus was the first dinosaur to be named from North America. A skeleton without a skull was collected from new Jersey and duck-billed shape, like anatosaurus and edmontosaurus. There was a rounded hump in front of the eyes and above the nostrils.

 

Heterodontosaurus

HET-er-oh-DON-toh-SAW-rus

Different toothed reptile

Ornithischia: Ornithopoda

Late Triassic/early Jurassic

South Africa

Heterodontosaurus is the best-known early ornithopod. Seven diffrent hetrodontosaurids have been named from southern Africa, Argentina amd China, but these are mostly based on discoveries of jaw pieces. Hetrodontosaurus is known from a good skull and skeleton. It had three diffrent kinds of teeth: sharp cutting teeth at the front, fangs , and broad, ridged cheek teeth. This kind of arrangment is unusual far a dinosaur. Most dinosaurs had only one kind of tooth. Humans have three kinds, just like Heterodontsarus. Heterodontosaurus was about 4ft (1.2m) long, and it was an active animal that could run on it hind legs.

 

Hypacrosaurus

Hie-PAK-roe-SAW-rus

Very high-ridged reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada, and Montana, USA

Hypacrosaurus was a large duck-billed dinosaur, about 30ft (9m) long. It was an advanced form, elated to corythosaurus and lambeosaurus. Hypacrosaurus had a short, high skull and its crest was rounded, but lower and fatter than that of Corythosaurus. The crest pointed backward into a solid bony spike. Hypacrosaurus had dozens of strong teeth which formed a large area for grinding and chopping tough vegetation. As the teeth wore down they were replaced by new ones.

 

Hypsilophodon

Hip-si-LOAF-oh-don

Ornithis: Ornithopoda

Early Cretaceous

Southern England

Hypsilophodon is an interesting medium-sized ornithopod. It was 7.5 (2.3m) long. It had short arms, each with five fingers, and long legs, each with four toes. Hypsilophodon could run fast, and it had a long stiff tail, which it used for balance. It was once thought that Hypsilophodon climbed trees, but this is not likely since it could not grasp the branches. Hypsilophodon had no teeth at the front of its mouth, but only a bony «beak», and a row of sharp chopping teeth further back. It could have nipped plants off with its beak, and chopped them up with its check teeth.

 

Iguanodon

i-GWA-no-DON

Iguana tooth

Ornithischia: Ornithopoda

Early Cretaceous

Western Europe, Nort Africa

Iguanodon was the second dinosaur to be named – in 1925 Iguanodon was up to 30ft (9m) long and stood 16.5ft (5m) high. Iguanodon had strong hind limbs with three big toes, each with a hooklike nail. The hand and a spikelike thum, which was probably used as a weapon. The tail was flattend and stiff, and Iguanodon could have run well on its hind legs or walked on all fours. There were n oteeth at the front of the jaw – only a bony beak like that of hypsilophodon. The cheek teeth were strong and ridged. Iguanodon may have pulled plants into its mouth with its tongue, and nipped them off with its beak.

 

Lambeosaurus

LAM-bee-oh-SAW-rus

Lambes's (Canadia paleontologist) reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada, and Montana, USA

Lambeosaurus was a crested duck-billed dinosaur related to corythosaurus and hypacrosaurus. Lambeosaurus had a square-shaped crest that ponted forward and a long spine that pointed backward. The nostrils in the snout continued down through the crest, making a large hollow cavity. In some specimens of Lambeosaurus the crest was bigger than the skull. Lambeosaurus was big – about 50ft (15m) long – and its bones massive.

 

Lycorhinus

LIE-koe-RINE-us

Wolf snout

Ornithischia: Ornithopoda

Late Triassic/early Jurassic

Sout Africa

Lyxorhinus is an important, but very poorly known, dinosaur. It was one of the early orithopods. – a heterodontosaurid – and its close relatives are geranosaurus and heterodontosaurus. Lycorhinus was named in 1942 from part of the left jaw of a very small dinosaur. It shows a large tusk, and teeth as in Heterodontosaurus.

 

Maiasaura

MY-a-SAW-ra

Good-mother reptile

Ornithischia: Ornithopoda

Late Cretaceous

Montana, USA

Maiasaura is one of the most important dinosaur found recently. In 1978 and 1979, skeletons of adult Maiasaura were found with nests and babies. The mother was about 30ft. (9m) long, and the young animal only 40in (1m) long. The nests were made in mounds which were only 40in (1m) long. The nest were made in mounds which were 10ft (3m) across, and the eggs were arranged in several layers. In each layer the eggs, which were shaped lake sauseges , lay in circles like the spikes of a wheel. The mother Maiasaura clearly laid her eggs so that they were all kept warm until the young ones hatched out. However, the young animals that have been found were not hatchlings, so they were staying around the nest as they grew up. This has been indicated that these dinosaurs looked after their young.

 

 

Muttaburrasaurus

MUT-aBUR-a-SAW-rus

Muttaburra (where found reptile)

Ornithischia: Ornithopoda

Late Cretaceous

Queensland, Australia

Muttaburrasaurus is one of the very few dinosaurs known from Australia. It is a recent find and was named in1981. Muttaburrasaurus was 23ft. (7m) long and it was related to iguanodon or to camptosaurus. It had low, broad head, and it has been suggested that its teeth could have been used for chewing plants or meat. Earlier Australian dinosaurs show close simlarities with African and American ones , but by the late Cretaceous periodm Australia may have had its own particular animals. Like most late Cretaceous ornithopods Muttaburrasaurus was larger than its early Jrassic counterparts.

 

 

Othnielia

OTH-nee-EL-ee-a

Named after Othniel C. Marsh,

American paleontologist

Ornithischia: Ornithopoda

Late Jurassic

Western USA

Othnelia was a small dinosaur, only 4.5ft (1,4m) long. It was very similar to hypsilophodon, but there were small differences in the teeth. It was orihinally named Nanosaurus by Othniel C. Marsh in 1877, and was renamed in 1977.

 

Ouranosaurus

oo-RAN-oh-SAW-rus

Valiant reptile

Ornithischia: Ornithopoda

Early Cretaceous

Niger, West Africa

Ouranosaurus in one of the most interesting dinosaurs from Norh Africa. It was related to iguanodon, but had a tall sail down its back. The sail was supported by a fence of spines on the backbone – on on each vertebra. The sail was made of skin, and blood vessels must have flowed through it. It may have been used by Ouranosaurus to keep its body temperature constant. If it was too hot, it could lose heat through the sail, and if it was too cold, it could take in heat from the sun. Another dinosaur with a sail was the meat-eater spinosaurus.

 

Parasaurolophus

par-a-SAWR-oh-LOAF-us

Reptile with parallel-sided crest

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada, Utah and New Mexcico, USA

Parasaurolophus was one of the most bizzare duck-billed dinosaur. It had a long tubular crest that curved back from its snout for a distance of up to 6ft (1,8m). The nostrils were in their normal place at the front of the snout, and the breathing tubes ran right up the crest and back down again into the mouth. If you cut the crest open, you would find four tubes – two going up and two coming down. The crest may have been a signal to let another Parasaurolophus recognize a member of its own species. Also if Parasaurolophus breathed out strongly, it could have made a honk or bellow inside the crest.

 

Parksosaurus

PARKS-oh-SAW-rus

Parks's (Canadian palaeontologist) reptile

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada

Parksosaurus was one of the last surviving hypsilophodontids. Its earlier relatives include dryosaurus, hypsilophodon and zephyrosaurus. Parksosaurus is known from an incomplete skeleton. When this animal died, it was buried on its left side in the sand, and most of the other side of the skeleton was broken up and lost. Parksosaurus had large eyes and a relatively short thigbone. Parksosaurus was about 8ft (2,5m) long.

 

Prosaurolophus

pro-SAWR-oh-LOAF-us

Before Saurolophus

Ornithischia: Ornithopoda

Late Cretaceous

Alberta, Canada

Prosaurolophus was a large duck-billed dinosaur, up to 26ft. (8m) long. The skull was low and had a small crest which ran up from the tip of the snout. There was a small knob at the top of this. Prosaurolophus is supposed to have been a relative of saurolophus, which lived about five million years later.

 

Saurolophus

SAWR-oh-LOAF-us

Crested reptile

Ornitrhischia: Ornihtopoda

Late Cratecous

North America and Asia

Saurolophus was an advanced, duck-billed, crested dinosaur about 33ft. (10m) long. It is known from several skeletons. The animal had a large head with a pointed crest runnig backward. The snout was broad, and the top of the head sloped backward as a flat surface. The skull bones above eyes continued backward as a spike which stuck out behind the head. There were two species of Saurolophus: the North American and Asian. They were very similar, except the fact that the Asian one had longer skull and crest.

 

Scutellosaurus

Skoot-El-oh-SAW-rus

Little shield reptile

Ornithischia: Ornithopoda

Early Jurrasic

Arizona, USA

Scutellosaurus is an interesting early ornithopod that was named in 1981. Scutellosaurus had a short skull with ridged teeth for eating plants. Its hind legs were longer than the arms, but by a smaller amount than in most ornithopods. Scutellosaurus had a very long tail – about one-and-a-half times its total length of 4ft (1.2m). Scutellosaurus was armored with hundreds of small bony knobs set in the skin of its back. This kind of armor as not been found in its relatives, such as fabrosaurus.

 

Secernosaurus

Se-SER-no-SAW-rus

Severed reptile

Ornithischia: Ornithopoda

Late Cratecous

Argentina

Secernosaurus is one of the few duck.billed dinosaurus known from South America. Most duck bills lived in North America and Asiam and this South American duck-bill shows that there was a land connection which dinosaurs could cross. Secernosaurus probably had a flat head like edmontosaurus or shantungosaurus. The skeleton, named in 1979, shows that Secernosaurus was a small duck-bill, probably only 10ft (3m) long.

 

Shantungosaurus

Shan-TUNG-oh-SAW-rus

Shantung (where found) reptile

Ornithischia: Ornithopoda

Late Cratecous

Shantung, China

Shantungosaurus was an advanced, duck-billed dinosaur with a flat head. It was the largest of this group, being over 40ft. (12m) long. Shantungosaurus had a long, low skull, with a flat, duck-shaped beak and no crest. A nearly complete skeleton of Shantungosaurus was discovered in the 1970s. A grown man standing beside it just reaches its knee.

 

Troödon

TROE-o-don

Wound tooth

Ornithischia: Ornithopoda

Late Cratecous

Alberta, Canada, and Montana, USA

Troödon is a poorly known but very unusual animal. A pointed saw-edged tooth named Troödon in 1856, and in the 1940s more fossils seemed to show that it was the same as the bone-head stegoceras. Discoveries in 1979 and 1980 show that Troödon may have been related to hypsilophodon and parksosaurus. However, its teeth were sharp and like those of a heat-eater. If Troödon did eat meat, it would be the only ornithischian dinosaur to do so.

 

Tsintaosaurus

SIN-tow-SAW-rus

Reptile from Tsintao

Ornithischia: Ornithopoda

Late Craecous

China

Tsintaosaurus was a very strange duck-billed dinosaur. It had a tall horn on the top of its head, just between the eyes. The horn pointed forward and was hollow. The breathing tubes ran up the horn. Tsintaosaurus was large – about 33ft. (10m) long. It may be related to saurolophus or to parasaurolophus.

 

Zephyrosaurus

zef-EYE-roe-SAW-rus

West-wind reptile

Ornithischia: Ornithopoda

Early Cratecous

Montana, USA

Zephyrosaurus was rather like hypsilophodon, and is one of the few dinosaurs whose name begins with the letter “Z”. It was named in 1980 from a skull and a few vertebrae. Zephyrosaurus had small ridged teeth which were adapted for efficient chewing of plants. Zephyrosaurus was a two-legged animal, about 6ft. (1.8m) long.