In Wuhan's East Lake, the foothills of nanwang mountain, is located in the China University of Geosciences (Wuhan) Yifu Museum, this museum has a collection of more than 30,000 pieces of various geological specimens, including many extremely rare and precious exhibits, the Guanling Chuangkong Sea Lily fossil I talked about before is one of them, and we want to introduce another exhibit today: Liang's Guanling Ichthyosaurus Liangae.
<h1 class="pgc-h-arrow-right" data-track="2" > rich and cruel shallow world</h1>
In Guanling, Guizhou in the Late Triassic Period, about 220 million years ago, it was still a warm shallow sea, the seabed was covered with various sea lilies and brachiopods, large groups of ammonites swam in the water, Cyamodus the bean-toothed dragon exposed its nostrils to breathe fresh air, and Anshunsaurus dived in the sediment of the seafloor in search of mollusks.
The Liang guanling ichthyosaur fossil is also believed to be classified as the shastasaurus | of the genus Shastosaurus P. Martin Sander et al. / Plos One (2011)
At this time, a huge figure rushed out of the shadows and bit an ammonite with a sharp mouth kiss, and it skillfully bit the soft body of the ammonite out of the shell, and bit the ammonite meat into its mouth, with a proficiency like we eat fried snails. Ammonite's flesh and blood fragments floated in the sea, attracting a group of small animals to eat, ammonite's shell slowly sank to the bottom of the sea, it was a sea monster with a body length of nearly 6.5 meters, it leisurely swam into the shadows, ready to find its next prey...
This giant sea monster is the Liang's Guanling Ichthyosaurus, the protagonist of our story today.
Liang's Guanling fish dragon head bone | P. Martin Sander et al. / Plos One (2011)
The oceans of the Mesozoic Era are the world of giant marine reptiles, ichthyosaurs, finnosaurs, ground-dwelling crocodiles and dragons have returned to the ocean from land, and among these ocean giants, the first to go to the sea to eat crabs, no, the one who dominates the sea is the ichthyosaur.
The mesozoic marine reptile fight scene imagined in the science fiction novel "Journey to the Center of the Earth" | Wikimedia Commons
<h1 class="pgc-h-arrow-right" data-track="2" > great dynasty of ichthyosaurs</h1>
The story begins with the earth-shattering mass extinction at the end of the Permian. More than 96 percent of marine species were unable to see the Triassic sun during the cataclysm, and as the Earth's environment gradually recovered, so did marine life. About 250 million years ago, in the Hubei and Anhui regions, it was a warm and rich shallow sea, and the surface of the sea was inhabited by huge amounts of plankton, which nourished countless zooplankton, such as ammonites. The ancestor of the ichthyosaur, a semi-aquatic reptile, seems to have discovered the business opportunity to "go to the sea" and returned to the sea once again without hesitation.
Chaohu Ichthyosaurus fossil | Ryosuke Motani et al. / Plos One (2014)
The ichthyosaurs who have just set out to sea don't seem to figure out how to become the "overlords of the seven seas", and some of them, such as the soft-wristed short-snouted dragon Carterhynchus lenticarpus, have chosen to be like sea lions or seals, both to return to the land to bask in the sun and chase ammonites and fish in the ocean. Chaohusaurus, a ichthyosaur found in Chaohu Lake, Anhui Province, shows a different trend: their bodies have grown and taken on a streamlined shape, their fin-like limbs have gradually become smaller, their tails have become stronger, they look more and more like fish, and their mouths have become longer. And they evolved the ability to spawn and no longer need to return to land to breed, all of which shows that they have become more adaptable to life in the ocean.
Imaginary picture of the birth of an oviparous ichthyosaur | Ryosuke Motani et al. / Plos One (2014)
Although the body structure of the Utatsu Ichosaurus found in Japan still retains some of the characteristics of terrestrial reptiles, it has more characteristics of adapting to the marine environment, and at this time, the ichthyosaur may not be satisfied with surviving in the shallow sea near the coast, and has begun to move farther and deeper into the ocean.
With the passage of time, the ichthyosaur seems to be like a fish in the water, releasing the dragon into the sea, and it seems that there is no opponent in the ocean that can compete with itself. In the Guanling region, ichthyosaurs showed a very rich diversity, and a variety of different forms of ichthyosaurs were found in the Late Triassic strata: among them, Mixosaurus, who had a narrow and long body, relatively primitive limbs, and no obvious downward curvature of the tail; there were also Mixosaurus, whose body and neck became shorter, whose eyes became larger, whose dorsal vertebrae were arched, whose tail vertebrae were curved downwards, and whose limbs were paddle-like; and the large Guanling Ichosaurus.
<h1 class="pgc-h-arrow-right" data-track="2" > life ends on rocks</h1>
At this moment, this rich shallow sea is like a paradise for ichthyosaurs. This huge Guanling ichthyosaur caught a few more ammonites, at this time it was almost full, leisurely swinging its body, the sunset afterglow dyed the huge body of the Guanling Ichthyosaurus golden yellow, at this time it saw a small animal floating on the surface of the water not far away, it was a juvenile Ichthyosaurus. Whether or not to add this little guy to a "lavish dinner" is a matter of trade-off. Although the Qianyu dragon is not large, its speed and flexibility are far above that of the Guanling Ichthyosaurus.
The restoration of the Ichthyosaurus compares with the size of humans | Slate Weasel / Wikimedia Commons
Guanling Ichthyosaur finally decided to attack, using the cover of the reef to approach the Qian Ichthyosaurus from the rear. The juvenile ichthyosaur seemed to be injured, slapping his flippers very hard, barely floating on the surface. It seemed that the prey had been caught, and the Guanling Ichthyosaurus leaned against a huge reef rock, preparing to sprint towards the Qianyu Dragon in the shadow of the reef, when suddenly it found that there was a dark shadow larger than itself on the side, and it was rushing over quickly, it was a Guizhou ichthyosaurus.
At this time, the Guanling Ichthyosaurus was too late to dodge, the Guizhou Ichthyosaur crashed into its left abdomen at full speed, the huge impact force made the Guanling Ichthyosaurus crash into the reef rock at once, the sudden attack caught it off guard, and it desperately swung its body into the wilderness and fled...
Fossils found in Guizhou, China last year, and in the belly of the Guizhou ichthyosaur fossil, there is also the remains of a Xingyi xinpu dragon Xinpusaurus xingyiensis | Dayong Jiang et al. / iScience (2020)
Guanling Ichthyosaurus escaped until it could no longer swim, at this time bright red blood emanated from its mouth and nose, the impact of the Guizhou Ichthyosaurus was not serious, but the one that crashed on the rock damaged its internal organs, and when it desperately fled, the strenuous movement further deepened the injuries of the internal organs... More and more blood flowed from its mouth, it could no longer hold on, as the sun set, Guanling Ichthyosaurus was slowly swept into the dark deep sea by the current, it was soon covered with thick silt, the body quickly decayed, and the bones formed fossils.
With the change of the vicissitudes of the sea and the uplift of the Himalayas, Guizhou is no longer a rich ocean. The fossil of Guanling Ichthyosaurus was discovered by paleontologists, and this complete Ichthyosaur fossil was sent to the Yifu Museum of China University of Geosciences (Wuhan) to tell people about the glory of the Ichthyosaur family in the past.