The Anodontosaurus is one very interesting dinosaur to know about. It is an extinct genus under the Ankylosaurinae family. There are two different species coming under this toothless lizard genus, the Anodontosaurus lambei and Anodontosaurus inceptus.
It is said that these dinosaurs of the Ankylosaurinae subfamily walked on Earth during the Late Cretaceous period until the mid-Maastrichtian stage. The fossil remains have been discovered in Alberta, Canada, in the upper region of the Horseshoe Canyon Formation.
The discovery of the physical description of this Ornithischia member is not complete. Only a partial skeleton has been retrieved which consisted of the skull, teeth, armor, rings, tail club, and other significant body parts. The partial skeleton has been quite resourceful in extracting useful data with regard to this species of the Ankylosaurinae subfamily.
The name of this armored dinosaur is pronounced like 'An-o-dont-o-sore-us'.
The Anodontosaurus is a type of Upper Cretaceous ankylosaurid dinosaur of Alberta.
This dinosaur of Ankylosauria suborder existed between the Late Campanian to the mid-Maastrichtian stage of the Late Cretaceous period, which is about 72.8-67 million years ago.
These Late Cretaceous dinosaurs of the Ankylosauridae family became extinct about 67 million years ago.
The fossil remains of this dinosaur were found in southern Alberta, Canada. It was collected from the upper region of the Lower Horseshoe Canyon Formation. The Anodontosaurus is an Upper Cretaceous ankylosaurid dinosaur of Alberta.
Being a herbivore, we believe these specimens of the Ankylosaurid taxa roamed well-vegetated areas in search of food.
There is not much information collected on the way of life of these dinosaurs of the Anodontosaurus genus. They might have existed alone or in herds.
We unfortunately do not know about the lifespan of these ankylosaurids.
Unfortunately, there is not a detailed description present on the reproductive activities of this dinosaur from Alberta, Canada.
This dinosaur is an ankylosaurid of medium size. It was a ground-dwelling specimen. These quadrupedal dinosaurs had armor on most of the dorsal surfaces of their bodies. The specimen had a wide but pointed tail club located towards the end of the armored tail. The Anodontosaurus skull shows postocular caputegulae which are small bone plates present on the specimen's cranium and are located immediately behind the eye.
Coombs had valid reasons for his assertion about the AMNH 5266 specimen representing a juvenile species. He cited that the sacral ribs were not fused to the ilium and to the vertebrae, and also that the vertebral centra were also noticeably not fused to the neural arches. Some other features also supported his argument like the ungual phalanx of the dinosaur’s manus is noticeably not the widest at the proximal articular end, which is otherwise observed in the adult specimens. The specimen had long bones with smooth surfaces. The marked rugosities as seen on the adult and the femur head is comparatively less spherical and delimited from the adjacent portion of the dinosaur’s femoral shaft. The distal ends of the Anodontosaurus tibia, as well as the fibula, are clearly not fused to the calcaneum and the astragalus.
The discovery of only the partial skeleton of this dinosaur from Alberta, Canada, has been made. The exact number of bones hasn't been estimated.
There is no data present on the way this dinosaur from the Late Cretaceous period communicated. It can be assumed that like all other dinosaurs they used vocals and actions to communicate.
These ankylosaurid specimens grew up to a length of 16.4 ft (5 m). The Anodontosaurus size is 10 times the size of the Yamaceratops dorngobiensis.
We do not have the exact speed of this member of the Ornithischia order. However, due to the discovery of the armor on their bodies, we can assume that this toothless lizard was slow.
This Ornithischia member weighed 4,000-4,409.2 lb (1,814.4-2,000 kg).
The female specimen of this genus can be called an Anodontosaura, while the male can be called an Anodontosaurus.
A baby Anodontosaurus can be called a hatchling.
From the features and the analysis of the Anodontosaurus tooth structure, the data has deduced that this armored dinosaur of order Ornithischia, Ankylosauria type was a herbivore. These ankylosaurid dinosaurs diet consisted of food including plants and vegetation.
There is no detailed description available on the lifestyle of this Ankylosaurinae. The Anodontosaurus is known to have shared its habitat with many other dinosaurs, some of them being the Anchiceratops, Hypacrosaurus, Pachyrhinosaurus, and Saurolophus. From this, it can be assumed that they were not very aggressive or territorial.
The Anodontosaurus dinosaur was named in 1928 by American-Canadian fossil collector and paleontologist Charles Mortram Sternberg. This name was based on the CMN holotype - CMN 8530, which is a partially preserved skeleton consisting of the dinosaur’s skull, armor, half ring as well as other postcranial remains. The Anodontosaurus skeleton procured was in a bad condition and it was almost crushed. This skeleton was obtained in 1916 by Sternberg from a quarry of the Canadian Museum of Nature, which is located about 8 mi (12.9 km) away from Morrin.
In 1986, Coombs carried out an extensive examination on the AMNH 5266 specimen, which was then referred to as Euoplocephalus, and concluded that it was a juvenile species. The skeletal system consisted of a neural arch, five vertebral centra, a single dorsal and two sacral ribs, the entire complete right hindlimb, the right ischium, a complete right pes, an incomplete left pes, along with other smaller fragments. The AMNH 5266 specimen was originally found at the Red Deer River in 1912. The holotype was collected by many researchers including Barnum Brown, Charles M Sternberg, George Olsen, and Peter Kaisen from the Horseshoe Canyon Formation.
The Anodontosaurus validity was quite a long discussion, which was formalized properly in three different studies. The first one was published in the year 2013 by Paul Penkalski and William T. Blows, which revalidated the Scolosaurus too.
The second study was also carried out in 2013 by Penkalski, which named and described the Oohkotokia specimens from Montana based on the fossil remains which were earlier considered to be the Euoplocephalus. He carried out a phylogenetic analysis of a few exclusive Ankylosaurine specimens. Of these specimens, the only Anodontosaurus participant in the analysis was the holotype. The Anodontosaurus was placed with the Euoplocephalus holotype in a polytomy, while the Oohkotokia was pushed into a clade with Dyoplosaurus, along with other specimens which were thought to be representing either the Scolosaurus or the Dyoplosaurus.
Walter Coombs, in 1971, proposed that only a single species of ankylosaurid existed during the Campanian Late Cretaceous Period in North America. He considered the Scolosaurus cutleri, Dyoplosaurus acutosquameus, and the Anodontosaurus lambei synonymous with the Euoplocephalus tutus. The synonymous relationship between the Euoplocephalus tutus and the Anodontosaurus lambei was accepted generally by all, and the CMN 8530 holotype was assigned to Euoplocephalus tutus.
However, the Dyoplosaurus was redesignated as a separate valid genus by Arbour et al in 2009. In the 2010 SVP Conference, an abstract presented by Victoria Arbour et al took the Anodontosaurus specimens and them distinct from the Euoplocephalus due to the distinctive cervical half ring ornamentation, skull, and even the tail club morphology, which includes the presence of the pointed, triangular knob osteoderms noted in the Anodontosaurus. She reassigned all the Ankylosaurine specimens of the Horseshoe Canyon Formation which were prior referred to as Euoplocephalus, as members of Anodontosaurus.
Based on the data available, Victoria Arbour and Philip Currie presented the phylogenetic analysis of the subfamily Ankylosaurinae in 2015, which is still being used.
The generic name of the Anodontosaurus dinosaur translates to ‘toothless lizard’ in Ancient Greek/ This name came from the observation that the compression damage to the dinosaur extracted the animal’s teeth, at the same time moving around various round elements below the dinosaur’s skull and even on top of the left side of the lower jaw. This ambiguity misled Sternberg in assuming that the teeth of this species were actually large trituration plates.
The specific name of this dinosaur, lambei, is titled in honor of the Canadian geologist and palaeontologist, Lawrence Morris Lambe from the Geological Survey of Canada, where the dinosaur holotypes were said to be reposited.
There are two specimens under this type, A. inceptus and A. lambei. From the results of Victoria Arbour’s SVP abstract of 2010, Philip Currie and Victoria Arbour formalized the revalidation of the Anodontosaurus. One of the specimens from the Dinosaur Park Formation was referred to as the Anodontosaurus dinosaur. This specimen of the Dinosaur Park Formation was later titled the A. inceptus holotype, a new species.
Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! Learn more about some other dinosaurs from our Pinacosaurus facts and Cryptosaurus facts for kids.
You can even occupy yourself at home by coloring in one of our free printable Anodontosaurus coloring pages.
Main image by Peter Menshikov