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Kidadl Team

SEPTEMBER 20, 2021

Did You Know? 15 Incredible Kritosaurus Facts

Incredible Kritosaurus facts that you might enjoy

A Kritosaurus is a flat-headed duck-billed dinosaur of the new genus, Hadrosaurid dinosaurs from the Dinosauria clade and order Ornithischia. During the Late Cretaceous period of North America, this dinosaur lived 74.5-66 million years ago. The name is translated to 'separated lizard' however, it is often mistaken as 'noble lizard', when referring to its supposed Roman nose. This dinosaur is a hadraosaur, the name given to duckbilled dinosaurs. As part of a follow-up expedition to a previous expedition, Barnum Brown (1910) discovered a new specimen of Kritosaurus (AMNH 5799) near the Ojo Alamo Formation in San Juan County, New Mexico, the United States. He took a few years to discover stratigraphy, but by 1916 he was able to establish that this dinosaur was from the Kirtland Formation of the Late Campanian age. A significant portion of the skull was reconstructed by Brown, in the aftermath of renaming it Kritosaurus edmontosaurus and Kritosaurus marginatus, eliminating many fragments, but he noticed that some pieces are different. This is attributed to crushing that these differences exist. Later, Jan Versluys intentionally leaked the former name, Nectosaurus. Kritosaurus navajovius ended up being the combination even though he retained the specific name.

A more arched nasal crest, similar to that of Gryposaurus, was added to the earlier reconstruction. Charles Gilmore supported his move to synonymize Greyposaurus with Kritosaurus as well. Through the '20s, this synonym was used, and after the 1942 Monograph on North American Hadrosauroids by Richard Swann Lull and Nelda Wright, it became standard. Kritosaurus was composed of at least the type species K until 1990. K.navajovius, K. incurvimanus, and K. notabilis, were Gryposaurus former type species. As a result, Lull and Wright have withdrawn their assignment to Kritosaurus of Hadrosaurus breviceps, described from dentary found in the Judith River Formation of Montana. Early in the '80s, this hadrosaurus was regarded as the relative of Kritosaurus and Gryposaurus, or both, particularly in semi-technical dinosaur dictionaries. According to David B. Norman's 'The Illustrated Encyclopedia Of Dinosaurs', the discovered material (Gryposaurus) is a Kritosaurus from Canada, although mounted skeletons identify this hadrosaurus as a Kritosaurus.

If you like reading about the Kritosaurus, you might also like the Rahonavis and the Heterodontosaurus.

Kritosaurus Interesting Facts

How do you pronounce 'Kritosaurus'?

The word Kritosaurus Dinosauria, Ornithischia order is pronounced as KRIT-oh-SAWR-us.

What type of dinosaur was a Kritosaurus?

The Kritosaurus (Kritosaurus navajovius) is a newly discovered genus of Hadrosauridae, a flat-headed duck-billed dinosaur.

In which geological period did the Kritosaurus roam the earth?

During the late Cretaceous Period in North America, it lived about 74.5-66 million years ago. This dinosaur existed from the Santonian Age to the Maastrichtian Age

When did the Kritosaurus become extinct?

The dinosaur Kritosaurus lived on Earth for 165 million years before they went extinct, about 65 million years ago at the end of the Cretaceous period.

Where did a Kritosaurus live?

According to fossil recovery, it is believed that these dinosaurs lived in Argentina. Barnum Brown (1910) discovered the new type specimen of Kritosaurus (AMNH 5799) in San Juan County, New Mexico, during a follow-up expedition to a previous expedition. 

What was a Kritosaurus's habitat?

Marine deposits across the middle of North America were left by a shallow sea during the Cretaceous period. The Chinese and Mongolian populations of hadrosaurs also exist. A wet environment existed during the Cretaceous period in the Gobi desert that included rivers and streams, offering a diverse habitat. A lack of eggshell material has been observed in areas where juvenile bones have been found. The scant remains of tiny hadrosaurs no longer constrain their habitat due to discoveries, acidic water flowing through bone beds, and collection bias.

Although the breeding locale remains inconclusive, dinosaurs are considered to have lived in uplands as well as lowlands. There might have been slight differences in habitat preferences among different species of dinosaur. A Hadrosaur becomes a small version of an adult hadrosaur. The juvenile body is proportionately smaller than that of an adult. Very small hadrosaur footprints have been found in the Blackhawk Formation of Utah. Barnum Brown (1910) discovered a new dinosaur specimen of a Kritosaurus (AMNH 5799) near the Ojo Alamo Formation in San Juan County, New Mexico, United States.

Who did a Kritosaurus live with?

Like other dinosaurs in this group, the Kritasaurus dinosaur lived in groups of several hundred animals. The Deinosuchus vs Kritosaurus were believed to have a predator and a prey relationship.

How long did a Kritosaurus live?

The life span of a Hadrosaurus, a flat-headed duck-billed species is reported to be up to 25 years old in several publications.

How did they reproduce?

Kritosaurus dinosauria of Ornithischia order nesting habitat has been understood in part by studying dinosaur park formations. There is evidence that invertebrate shells acted as buffers in the acidic waters of the lowlands. A great deal of bone and dentary material has been recovered from the lowlands. In addition, fossils show no signs of abrasion, suggesting they were preserved near their resting places. Clam and snail calcium carbonate shells provided a higher pH that prevented the complete decay of hadrosaur eggshells, which have a pebbly texture.

Scientists suspect that hadrosaur nesting grounds may have come into existence as a result of the discovery of preserved nests. Many species of birds would have displayed this behavior. 25 juvenile hadrosaurs were collected from the Two Medicine Field in 1978. Maiasaura means 'good mother lizard' and it is located in western Montana. These little dinos had eggs in their shells and they were all of the same species and age. They were considered nestlings. A nest could not have held adults who were too big. Covering the eggs with vegetation was thought to keep them warm. Crocodiles use the same technique. Fermenting plants provided the heat that dinosaur eggs needed. Fruit and bits of vegetation would have been delivered to the nest as soon as the eggs hatched. Hatchlings were 14 in (35.6 cm) in length and 1.5 lb (0.7 kg) in weight.

Kritosaurus Fun Facts

What did a Kritosaurus look like?

The Kritosaurus length is 30 ft (9.1 m). Only partial skull and jawbones, along with postcranial remains, characterize the Kritosaurus, the type specimen. The muzzle and upper part of the beak are missing. At the back of the skull, the quadrate articulates with the lower jaws extending 34 in (86.4 cm) in length from the tip of the upper beak to the base of the quadrate that articulates with the upper beak at the front. The Kritosaurus can be recognized by its predentary lower beak without tooth-like crenulations, its downward curve to its lower jaw near the beak, and its somewhat rectangular maxilla (upper tooth-bearing bone).

According to the original description of the Kritosaurus skeleton skull of Anasazisaurus, the crest is formed by an upward-pointing tab or flange of bone rising internally between and above the eyes and folding back underneath. Unlike similar hadrosaurs like the Gryposaurus, this dinosaur has a distinctive crest. Approximately 35 in (88.9 cm) of the Kritosaurus skull is preserved in its entirety, with the top of the crest roughened. Based on further investigations, the Kritosaurus can be distinguished from other genera by a long dorsolateral margin of the maxilla. In comparison with the infratemporal, the jugal has a deeper orbital constricting. Having a dorsal margin considerably higher than that of the orbital margin, the infratentorial fenestra has a greater radius than the orbit in adults. As with the orbital margin, the frontal bone is joined to the nasal bones by two caudal parasagittal processes.

There is a Kritosaurus dinosaur flathead reconstruction preserved in the American Museum of Natural History.

How many bones did a Kritosaurus have?

Only partial skull, jaw, and postcranial remains are known by scientists. In addition to the muzzle and upper beak, also missing is part of the eyes, and a crest formed by fragments of the skull that was not previously placed. The Kritosaurus tooth possesses a pronounced downward bend for the lower jaw, and an inferior maxillary (upper tooth-bearing bone) with no crenulations may have existed.

How did they communicate?

The Kritosaurus dinosaur has a nasal crest that might have been used to describe the sex of individuals or to track social standing. For both visual and auditory signaling, there may have been inflatable air sacs flanking it.

How big was a Kritosaurus?

A Kritosaurus size is about 30 ft (9.1 m).

How fast could a Kritosaurus move?

Scientists have estimated the speed of local Kritosaurus based on prints of Kritosaurus feet found in a dinosaur trackway in Wyoming at 3–5 mph (4.8-8 kph).

How much did a Kritosaurus weigh?

The Kritosaurus weighs almost 4 lb (1.8 kg).

What were the male and female names of the species?

There is no specific name giving to the separate sexes, they are simply referred to as the female Kritosaurus and the male Kritosaurus.

What would you call a baby Kritosaurus?

A baby Kritosaurus is called a hatchling.

What did they eat?

Kritosaurus dinosaurs had a herbivorous diet and were used to eating plant material in this diet. They did not hunt.

How aggressive were they?

A male dinosaur often exhibits aggressive behavior when they compete for a female dinosaur, according to details studies. Scars on adult males' heads attributed to tusk use have been found on those with broken tusks.

Did you know...

There is a possibility that the Hadrosauridae was able to outrun a T-rex.

The Kritosaurus raised their young, as evidenced by fossilized nests and hatchlings.

Kritosaurus dinosaur flathead reconstruction is preserved in the American Museum of Natural History.

Details about a new dinosaur specimen of the Kritosaurus (AMNH 5799) was found in New Mexico, United States.

Kritoaurusare ornithischians were quite small at the time of emergence but developed into very large animals during the Cretaceous Period. Their number was greater than sauropods.

How did the Kritosaurus get its name?

The Kritosaurus name means 'separated lizard' which is sometimes mistranslated as 'noble lizard'. This name is to do with the presumed 'Roman nose' of these skulls arranged in separate parts, meaning the arrangement of the cheekbones.

How many teeth did the Kritosaurus have?

There were hundreds of teeth in a hadrosaur's mouth, arranged like a battery.

Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other creatures from our Yinlong facts, or Crichtonsaurus facts for kids.

You can even occupy yourself at home by coloring in one of our free printable singing dinosaur coloring pages.

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