Mastonzaur (lat. Mastodonsaurus) a giant representative of the labyrinthodontists. Belongs to the detachment of the darkospoles, the submarine. Includes two types:
Near the German Stuttgart in the 1920s of the 19th century many bones were found related to the Triassic, the first period of the Mesozoic era. Among the finds there was a strange tooth about 10 centimeters long, several fragments of the skull and other bones.
Georg Friedrich Yeger named the animal, which belonged to the listed remains, Mastonzaurus and attributed him to dinosaurs. (Dinosaurs then understood almost all prehistoric animals, the appearance of which was reminiscent of reptiles). After some time, other bones of this ancient creature were discovered, and it turned out that it was a prehistoric amphibian.
Around 1840, similar skull bones were found in England along with a femur and one vertebra. From that moment on, the history of the Mastodonsaurus began to become more complicated. Paleontologist Richard Owen, known as the scientist who coined the name “dinosaur”, suggested that the skull, bones and vertebrae belonged to the same animal.
True, the femur was very large compared to the skull, which in its length approximately corresponded to the skull of a two-meter crocodile, while it itself corresponded to a crocodile 7-8 meters long. Owen explained this by saying that this animal was a kind of giant frog, which, accordingly, should have had large and muscular hind limbs.
To further complicate the issue with the classification of this creature, Owen replaced the name “mastodonsaurus”. Yeager chose this name because it means “palipet-toothed dinosaur,” a fitting term for a tooth that had an oddly shaped tip.
Two such large teeth were located on the lower jaw of the animal, and in its upper jaw there were holes corresponding to them. So, Owen thought the name “Mastodonsaurus” was too banal, it looked too much like the name of a giant prehistoric elephant, a mastodon. Therefore, he proposed a new name “labyrinthodont”, that is, labyrinth tooth. (At that time, renaming prehistoric animals was much easier than it is today, since modern scientists adhere to strict rules.
International Code of Zoological Nomenclature (ICZN); so, the prehistoric whale Basilosaurus was first considered a reptile hence the name “royal lizard”, and then, when it was found out that it was not a reptile, it was renamed Zevglodon, although in our time it is again called Basilosaurus).
True, the name “labyrinthodont” was also chosen very well the fact is that a few years before that it was noticed that the teeth of the Mastodonsaurus (and its relatives) had a very complex, labyrinth-like, structure of tooth enamel and dentin in cross section. It is assumed that this alternation of tooth enamel and dentin, as in the composite material, was mechanically beneficial in increasing the flexibility and strength of the teeth.
Finally, in the second half of the 19th century, it turned out that Owen was mistaken, and the bones, apparently, belonged to another animal. Thomas Henry Huxley, who disliked Owen for rejecting Darwin’s theory of evolution, said he “would not advise geologists to suggest that there is any evidence that labyrinthodonts were frog-like animals.”.
Thus, labyrinthodonts, including Mastodonsaurus, did not look like a frog. However, it seems that the concept of the frog-like essence of the Mastodonsaurus is firmly entrenched in the minds of scientists. Although in the reconstructions of this animal they abandoned the long frog-like hind limbs, otherwise its body very much resembles that of a frog.
However, if we accept such a structure of the Mastodonsaurus, then the question arises how such an animal could live, because the tiny, stump-like paws were clearly insufficient for him to run, and the tail was not particularly good for swimming.
According to newer research, this creature had a completely different appearance. At first glance, the “new” Mastodonsaurus looks like a crocodile, which is why it is sometimes called a crocomander, a mixture of a crocodile and a salamander. However, upon closer examination, of course, significant differences are found: for example, most of the teeth are much smaller than those of a crocodile, the skull is flatter and does not have openings typical of reptiles, the limbs are smaller and thinner than those of a crocodile.
Apparently, the mastodonsaurus crocommander was still poorly adapted for running on land, while crocodiles are quite capable of overtaking a running person. It is assumed that he devoured everything that he managed to grab, that is, not only fish, but also careless reptiles or other related amphibians, which were found in abundance during the Triassic period.
Apparently, he had no natural enemies, since adult mastodonsaurs reached 5 meters in length. So from what was initially supposed to be a giant frog and a clumsy, short-legged monster, the image of a rather elegant and dynamic creature eventually arose.
Mastodonsaurus is an interesting animal for one more reason: in paleontology, they often talk about the “age of amphibians”, “age of reptiles”, “age of mammals”, etc.d. The Triassic period, during which mastodonsaurs lived, refers to the Mesozoic era, that is, the era of reptiles. However, then the ecological niche that today belongs to crocodiles was occupied not only by reptiles (although they were also present there, for example, phytosaurs), but also by mastodonsaurs and their relatives.
