Ichthyosaurs are iconic marine reptiles of the Mesozoic. Their discovery in England at the beginning of the 19th century and theirstudy by the greatest names of the natural sciences (Blainville, Owen,Cuvier ...) have contributed to the conceptual revolution of Earth’s history.
AN INTRODUCTION TO ICHTYOSAURUS
The newspapers of that time and the novels of Jules Verne helped topromote the ichthyosaurs to the rank of antediluvian monsters, fiercefighters in an infernal world. They have become underwater stars, equal to their terrestrial dinosaur counterparts. Since the end of the19th century, discoveries multiplied. Today, most of the major naturalhistory museums have at least one ichthyosaur fossil.
Just as dolphins descended from land mammals that adapted to live in the sea, the ancestors of ichthyosaurs were reptiles that lived on land. The limbs of ichthyosaurs are characterized by a considerable reduction in the size of the long bones and a very high number of phalanges. The result is a highly flexible fin. The fins of dolphins have the same adaptations.
Many details of ichthyosaur anatomy reveal their extensive adaptation to aquatic life. Most fast-swimming animals have a fusiform body shape, with a tail that serves as a means of propulsion, while the fins serve to manage direction. Thus ichthyosaurs, dolphins, and sharks are not related to each other, but all have similar morphologies.
The teeth of ichthyosaurs regrew throughout their life. Larger species had stubby conical teeth intended for crushing bones, while smaller ichthyosaurs had thin teeth organized into combs to capture small and agile prey.
Scars bear witness to the brutal life of the ichthyosaurs. They confronted other large marine reptiles such as plesiosaurs and pleiosaurs, and the largest species even turned out to be cannibalistic.
As it was impossible for Ichthyosaur to come on land to give birth, they developed viviparous adaptation and gave live birth in water. As with current dolphins, the tail of the babies came out first to prevent the young from drowning during childbirth. As soon as a baby was released, we can assume that its mother pushed it to the surface to help it take its first breath.
The species of Stenopterygius had a small skull and narrow flippers.Its skull was extended into a beak and was armed with an array oflarge sharp teeth. The limbs are perfect fin-like structures. The tailterminated in a large, semicircular, leathery, vertical caudal fin andeven a triangular dorsal fin was present.
This species of Ichthyosaur,in particular, has not been studied in depth and there is very littleliterature on it. Therefore, the present offering represents a uniqueand interesting opportunity for a museum or private collector toconduct further scientific research.
Extraordinary skill and precision not only enabled the tedious extraction of the fossilized bones one by one from its matrix, but also made it possible to rebuild the skeleton in 3D. Only a handful of ichthyosaurs have ever been reconstructed this way. This individual specimen represents more than two years of work by a specialist.
The skull of the specimen shows a wonderful preservation, only few teeth and the sclerotic ring have been restored. The shoulder grindle is complete and carries the forelimbs composed of original humeri, radius, ulna, metacarpals and 65% of original phalanges. Of the pelvic bones, pubis and ischium are original, and the hind limbs are 100% complete.
Overall, this makes this skeleton extremely complete with a total of more than 80% original bones. It is the first time that a complete specimen like this, found in France, will be up for auction