Lambeosaurus ‭(‬Lambe’s lizard‭ ‬-‭ ‬after the palaeontologist Lawrence Morris Lambe‭)

Short Info

Lambeosaurus ‭(‬Lambe’s lizard‭ ‬-‭ ‬after the palaeontologist Lawrence Morris Lambe‭)

Phonetic : Lam-be-o-sore-us.

Named By : William Parks‭ ‬-‭ ‬1923

Diet : Herbivore

Size : Estimated 9 meters long

Type of Dinosaur : Euornithopod

Type Species : L.‭ ‬lambei‭ (‬type‭)‬,‭ ‬L.‭ ‬magnicristatus

Found in : Canada‭ ‬-‭ ‬Alberta.‭ ‬USA‭ ‬-‭ ‬Montana.‭ ‬Possibly also Baja California

When it Lived : Late Cretaceous, 76-74 million years ago

Lambeosaurus (/.laembi@’so:r@s/LAM-bee–@-SAWR–@s) is a genus hadrosaurid dinosaur. It lived approximately 75 million years ago in North America’s Late Cretaceous (Campanian phase), of the Late Cretaceous period. The distinctive hollow cranial crown of this bipedal/quadrupedal herbivorous dinosaur is well-known. It resembles a hatchet in the most well-known species. There are several possible species, including those from Canada, Mexico and the United States. However, only two Canadian species are recognized as valid.

Lambeosaurus ROMRobin Zebrowski, CC BY 2.0, via Wikimedia Commons

Lawrence Lambe first identified material relevant to the genus in 1902. William Parks in honor of Lambe came up with the modern name in 1923. It was based on better preserved specimens. Because small-bodied crested hadrosaurids that are now considered juveniles have been previously thought to be part of their own species and genera, the genus has a complex taxonomic history. The skulls of L. lambei type species are currently interpreted to show age differences and sexual dimorphism. Lambeosaurus was closely related with the more well-known Corythosaurus. It is also found in slightly older rocks as well as the lesser-known genera Hypacrosaurus or Olorotitan. All three had unusual crests that are now thought to have served social functions such as noisemaking or recognition.

Lambeosaurus was best known by L. lambei. It looked very similar to Corythosaurus except for the head ornamentation. The crest of Lambeosaurus had a different shape to Corythosaurus’s. It was placed forward and the hollow nasal passages were at the front. They were stacked vertically. It can also be distinguished from Corythosaurus because it lacks forking nasal processes. This is the only way you can tell the juveniles of both genera apart. As the animals grew older, the crests changed to their unique forms.

Lambeosaurus, like other hadrosaurids could move on all fours. This was evident by the footprints of closely related animals. The tail was stiffened by ossified tendon which prevented it from drooping. It had four fingers. The innermost finger of the five-fingered generalized tetrapod hand was missing. However, the second, third and fourth fingers were bundled together and had hooves. This suggests that the animal may have relied on the hands for support. The fifth finger could be used for manipulating objects and was left free. Only the three central toes were present on each foot.

The most distinguishing feature, the crest was different between the two species. L. lambei’s crest was a hatchet-like form when the dinosaur was fully grown. It was shorter and more round in female specimens. The “hatchet knife” was visible in front of the eyes. The “handle”, a bony rod that extended over the skull’s back, was a solid bone rod. The “hatchet knife” consisted of two parts: the top was a thin bony coxcomb that grew late in life. The lower portion contained hollow spaces that were continuations from the nasal passages. L. magnicristatus had the “handle” reduced and the “blade”, expanded to form a tall pompadour-like crown. The front half of this crest has been lost in the most damaged specimen.

Large adult Lambeosaurus specimens have been measured at 7 m (23 feet) in length. Multiple specimens have been photographed with impressions of scales. A specimen currently assigned to L. lambei showed a thin skin and uniform, polygonal, scutes that were distributed in an undetermined order on the neck. The torso, tail, and neck. Similar scaling is evident from L. magnicristatus’s neck, forelimb and foot.

Source: Wikipedia