Ichthyosaur: a giant 180-million-year-old fossil of a "sea dragon" found in a UK tank. Sea dragon: habitat and characteristics
Discovered in a reservoir in Rutland County in the English East Midlands, this specimen is the largest and most complete ichthyosaur. fossil Found in the UK, it is about 33 feet long and a skull weighing one ton.
It is also believed to be the first of its kind - Temnodontosaurus trigonodon - to have been found in Great Britain.
Marine reptiles that lived alongside dinosaurs, ichthyosaurs resemble dolphins in body shape. They became extinct about 90 million years ago, having first appeared 250 million years ago.
Ichthyosaurus was first discovered in February last year in the Rutland Water nature reserve by Joe Davis, leader of the Leicestershire conservation team and the Rutland Wildlife Trust, which manages the nature reserve in partnership with owner Anglian Water. .
Davis was doing a landscape remodeling chore, which includes draining water into the lake, when he spotted fragments of vertebrae protruding from the mud, Leicestershire and the Rutland Wildlife Trust said in a statement. press release .
This was then followed by extensive excavations in August and September by a team of paleontologists, led by Dean Lomax, an ichthyosaur expert and current visiting scientist at the University of Manchester.
"Its size and completeness combined are what makes it truly exceptional," Lomax told CNN, adding that previous ichthyosaur finds in the UK "weren't that big and perfect."
Lomax said it was the most complete large specimen - which he classified as 10 meters or more in length - found globally. He said it was a "truly surprising discovery" and, for him, "a highlight of his career".
"This was at the top of the food chain, at the top of the predators," he told CNN of the discovery. "So this one would have fed on other ichthyosaurs, he would have eaten a big fish, he would have eaten, if he could have caught them, even squid".
However, Lomax said the find was "the tip of the iceberg," with much to be discovered in the specimen after the pieces of rock were removed, with the possibility that the ichthyosaur's last meal may have been preserved or even that the reptile may have been pregnant.
"It was great," Anglian Water spokesman Reagan Harris told CNN. “I mean, you really couldn't believe your eyes when you looked at them in front of you. But yes, incredible. "
Smaller ichthyosaurs were previously found at the Rutland Water site, said Harris, who was located at the excavation site, but the "huge size" and "well-preserved" nature of this particular find made it unique.
The Ichthyosaur Rutland was "probably one of the largest fossil reptiles ever found, including dinosaurs," said Paul Barrett, research fellow in the Department of Vertebrate Paleobiology and Earth Sciences at the Natural History Museum in London. Barrett was not involved in the discovery.
"It's really, really impressive," Barrett told CNN. "Certainly one of the UK's most impressive marine fossil discoveries that I can remember at least in the last 20-30 years or so."
Barrett, whose work involved dinosaurs and other extinct reptiles, including ichthyosaurs, said the discovery underscores the "universalism" of the species, previously known primarily in Germany.
The specimen is currently being worked on by a fossil restoration specialist, a process that will take 12-18 months. So, Harris said, the goal would be to make it public.
"We are very proud of that, and I know the local community is too," he told CNN. "We would love to take it home to Rutland and show it to people for fun."
For Lomax, the lead researcher, one hope is to further explore the Rutland Water site, where six or seven vertebrae of other ichthyosaurs were discovered during the excavation.
He said the fact that "things that happened by chance actually made this discovery" hadn't escaped him.
"Honestly, it's incredibly unusual," Lomax told CNN. "Enthusiastic fossil hunters or paleontologists, they can search in their entirety and find nothing like it, even when you know where to look."
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Sea dragon: habitat and characteristics
Summary
• Habitat of the sea dragon
• Physical characteristics
• Behavior of the sea dragon
• Diet
• Reproduction
• State of conservation
The sea dragon ( Phyllopteryx taeniolatus ) is a fish from the Syngnathidae family , which also includes seahorses and pipefish. Signatidae represent a total of 307 species, divided into 57 different genera. The sea dragon is one of 2 members of the genus Phyllopteryx , along with its relative the Red Sea dragon ( Phyllopteryx dewysea ).
These animals attract attention for their alien morphology and their unique habits, very different from those of the rest of the actinopterygian peas. If you want to know more about them, read on.Habitat of the sea dragon
As we have said, the sea dragon is a signatid. All members of this family are marine and inhabit the tropical seas of the world, and most species occupy coastal and shallow waters, although there are some that enter open ocean areas. In addition, many of them are associated with algae of the genus Sargassum .
For its part, the sea dragon ( Phyllopteryx taeniolatus ) is endemic to the coastal waters of Australia, particularly the eastern Indian Ocean, the Southern Ocean and the western South Pacific Ocean. It is a species closely associated with rocky surface reefs, but is also found in prairies with abundant algal vegetation.
While these requirements may seem very generic, the sea dragon is highly specialized for living in a single type of environment. To accommodate a population, the waters must be between 12 and 23 ºC and the depth cannot exceed 50 meters. Typically these animals inhabit the water column 8-12 meters from the surface.
Sea dragons are highly specialized animals in the environment they live in. Minor changes in the ecosystem could favor its disappearance.Physical characteristics
All signatids are characterized by an elongated snout, fused jaws, absence of pelvic fins and because they are covered with hardened plates, like a bone armor. Due to their external protection, they are slower than other actinopterygians, although they have a surprising and very precise range of motion when swimming.
Phyllopteryx taeniolatus It reaches a maximum length of 45 centimeters and has a very elongated body, with a tubular head and mouth region. It has 2 very marked spines above the eyes and a variable number of dorsal appendages, which make it look like an alga. It also has a series of bluish vertical bands near the cephalic region and belly.
There are no subspecies of sea dragon, but this can be confused with one of its more immediate relatives - the foliate sea dragon ( Phycodurus eques ). This species differs from the one we are interested in today by presenting many more appendages and showing a lighter color.
Water dragons present strange bodies to perform cryptic mechanisms. Thanks to their appendages, they look like algae floating adrift in the water column.Behavior of the sea dragon
Thanks to the elongated body and body plates, this fish moves very slowly. Therefore, it only relies on its appendages and its shape to go unnoticed in the environment and not attract the attention of any predators. Sea dragons do not have a prehensile tail, unlike seahorses, so they are simply carried floating adrift.
They are very passive and peaceful animals with a reduced ability to maneuver in the water column. Although they do not have specific predators, their clumsiness can be very challenging: sometimes dead specimens are found stranded on the beaches. Furthermore, as studies indicate, they tend to be solitary fish, although pairs and groups are sometimes observed.Diet
Signatids have fused jaws in the form of a unique conical structure, so their mouth is shaped like a very elongated "tube". Consequently, they cannot chew or swallow in the typical ways used by other actinopterygii.
For its part, the sea dragon uses its muscles and mouth bones to suck its prey directly. The victims are very small, usually very small crustaceans -misidaceans and amphipods- belonging to the zooplankton community .Reproduction
These fish have fascinating reproductive behavior, because like seahorses, sea dragons have marked parental care from their father. According to the scientific journal Fish Biology, males are receptive from June-July to January, so the reproductive cycle is believed to be around 6 months long.
Once copulation has taken place, the female releases the eggs and the male places them in a special bag under the tail ( brood ), where they remain for about a month. The peak of pregnant males is reached in the months of November-December, at the end of the breeding season.
Each copulation brings back about 120 eggs, but the survival rate of the young is very low. Young specimens reach sexual maturity when they reach 32 centimeters in length.State of conservation
According to the International Union for Conservation of Nature , this species is of “Least Concern (LC)”. Despite this, their populations decline over time, presumably due to water contamination from the discharge of fertilizers and waste products. Being a coastal animal, you may notice the effects of pollutants more than others.
On the other hand, powders obtained after drying their bodies are also relatively in demand in traditional medicine markets. You've seen offers of $ 200 per gram of compound. Studies have also dated the threat posed by Scuticociliatida parasitic agents to populations of sea dragons, flute fish and seahorses.
Due to the local threats that threaten this beautiful fish, various conservation plans have been put in place at the local level. Additionally, species like this encourage respectful tourism, as thousands of divers come to Australia's shores each year to observe this and other wonderful animals.
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