Claosaurus
Herbivore·Late Cretaceous·Kansas, United States·Unknown
Claosaurus was a genus of hadrosauroid dinosaur that lived in North America during the Late Cretaceous Period. While once considered an early hadrosaurid, it is now understood to be the closest non-hadrosaurid relative to true hadrosaurids. Its name, meaning "broken lizard," refers to the fragmented state of its fossils.
Key Facts
- ›Lived during the Late Cretaceous Period (Santonian-Campanian).
- ›Originated from what is now North America.
- ›Its type and only valid species is Claosaurus agilis.
- ›Estimated to be an herbivore.
- ›Possessed an estimated length of 3.7 meters (12 feet).
- ›Its fossils were first discovered in the Niobrara Formation of Kansas.
- Estimated length of 3.7 m.
- Mass estimated to be comparable to a lion.
- Herbivorous dentition characteristic of hadrosaurs.
Edmontosaurus, Anatosaurus
North America
About Claosaurus
Claosaurus is a genus of hadrosauroid dinosaur that roamed North America during the Late Cretaceous Period, specifically the Santonian to Campanian stages. Its scientific name, meaning "broken lizard," reflects the fragmented nature of the fossils discovered, which were found in an unusual state of disarray. While initially classified as an early member of the Hadrosauridae family, more recent analyses suggest Claosaurus lies outside this group, representing the closest known non-hadrosaurid relative to true hadrosaurids within the broader clade Hadrosauromorpha.
Description and Discovery
The fossil record for Claosaurus is considered insufficient, consisting of minor skull fragments and a partial skeleton. This makes precise estimates of adult size challenging. However, one estimation places its length at approximately 3.7 meters (12 feet), with a body mass comparable to that of a lion. Like its relatives, Claosaurus was an herbivore, subsisting on plant matter. The first evidence of its existence was unearthed in 1871 in the Niobrara Formation near the Smoky Hill River in Kansas, United States, comprising both cranial and postcranial remains.
Classification and Species History
The type species, Claosaurus agilis, was first named by Othniel Charles Marsh in 1872 as Hadrosaurus agilis. It was later moved to its own genus, Claosaurus, in 1890 due to significant differences noted between the specimen and Hadrosaurus. Marsh also named a second species, C. annectens, in 1892, which has since been reassigned to the genus Edmontosaurus. A third species, C. affinis, described by G. R. Wieland in 1903, is considered dubious due to its fragmentary nature and issues with its type material, with some of its remains potentially being misidentified or mixed with other specimens.
Source: Wikipedia ↗
Frequently Asked Questions
What does the name Claosaurus mean?
The name Claosaurus comes from Greek words 'klao' (broken) and 'sauros' (lizard). It was named "broken lizard" because of the fragmented condition of its fossils when they were discovered.
When did Claosaurus live?
Claosaurus lived during the Late Cretaceous Period. Specifically, its temporal range falls within the Santonian and Campanian stages of this period.
What did Claosaurus eat?
Like other hadrosaurs, Claosaurus was an herbivore. This means its diet consisted primarily of plants.
Where were Claosaurus fossils found?
The initial evidence for Claosaurus was discovered in the Niobrara Formation, near the Smoky Hill River in Kansas, United States. This location yielded partial skull fragments and an articulated postcranial skeleton.
How large was Claosaurus?
The exact size of an adult Claosaurus is uncertain due to insufficient fossil remains. However, one estimate suggests a length of around 3.7 meters (12 feet) and a mass comparable to that of a lion.
Is Claosaurus a true hadrosaurid?
While traditionally classified as an early hadrosaurid, a 2008 analysis placed Claosaurus outside the clade containing true hadrosaurids. It is now considered the closest non-hadrosaurid relative to this group.
Related Dinosaur species
Ceratops
Ceratops is a dubious genus of herbivorous ceratopsian dinosaur from the Late Cretaceous period, known from fossils found in Montana's Judith River Formation. Despite its poorly understood nature, Ceratops holds historical significance as the type genus for both the Ceratopsia and Ceratopsidae groups. Its scientific name, meaning 'horn face,' reflects its most prominent feature.
Cionodon
Cionodon is a dubious genus of hadrosaurid dinosaur from the Late Cretaceous period. It is considered a nomen dubium due to being based on very fragmentary remains, making definitive classification challenging. Several species have been described, but many have been reclassified or remain poorly understood.
Bisticeratops
Bisticeratops is a genus of chasmosaurine ceratopsian dinosaur that lived during the late Campanian age of the Late Cretaceous period. Its fossils have been discovered in the Kirtland Formation of northwestern New Mexico, United States. The genus is known from a nearly complete skull, which displays evidence of healed tyrannosaurid bite marks.