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Texas is the home of a newly discovered wind dragon species

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A new genus and species of a large wind dragon that lived about 218 million years ago has been described from a large portion of its carapace discovered in Texas, USA.

Aerosaurus life restoration chest typothorax. Image credit: Smokeybjb.

Aitosaurus is an extinct quadrupedal heavily armored reptile aetosaurs.

Their name means “eagle lizard” and comes from the fact that their skull resembles that of a bird.

These creatures could reach lengths of up to 6 m (20 ft) and were geographically widespread during the Late Triassic.

“Aetosaurs are a group of quadrupedal armored reptiles whose terrestrial ecology is inferred to include both herbivory and omnivory,” said a paleontologist at the University of Texas at Austin. William Reyes and his colleagues.

“They have achieved a nearly global geographic distribution, but are stratigraphically restricted to the Late Triassic.”

“Most species of wind dragons reach a total length of 2 to 6 meters (6.6 to 20 feet).”

dubbing Garsapelta Murerithe newly identified species grew up to 3.5 meters (11.5 feet) long.

This extinct animal lived in what is now the United States during the Middle Triassic period, about 218 million years ago.

Hypothetical reconstruction of Garsapelta Mureri: (a) Carapace seen from the back, and (bf) cross-sectional view of the carapace seen from the back. Cross-sectional views of (b) posterior neck and anterior trunk, (c) mid-trunk, (d) posterior trunk and sacrum, (e) anterior caudal region, and (f) mid-caudal region. Arrows indicate anatomical direction. A – Anterior, D – Dorsal, L – Lateral, M – Medial. Image credit: Jeffrey Martz / Reyes other., doi: 10.1002/ar.25379.

Its fossilized skeleton was discovered. Cooper canyon formation Located in Garza County, Texas.

It was recovered with an associated carapace containing elements of both the left and right sides of the body.

The discovery of Garsapelta Mureri “This provides new insights into interspecific variation in the carapace of etosaurs,” the paleontologists said.

“It is clear that the morphology of the lateral osteoderm determines the final topological position of the bone. Garsapelta Murerirecover it as a sister taxon of . Desmatostini”

“The similarities between the two are Garsapelta Mureri, Rioaribascus chamensisand the paratipothrasin The discoveries from Colorado's Eagle Basin indicate a biostratigraphic range that we believe is probably limited to Revuelto's putative holochronozone (215 to 207 million years ago), but It suggests that we are working on the emergence of a new group of wind dragons that may be just as old. The latest Adamanian. ”

team's paper appear in anatomical records.

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William A. Reyes other. Garsapelta Mureri generation. Such. In November, a new species of wind dragon (archosaur: pseudosaur) was discovered in the middle Cooper Canyon Formation of the late Triassic (middle Norian) in the Dokum Group, Texas, USA, and the morphological characteristics of the wind dragon's carapace. its impact on our understanding of difference; anatomical records, published online on January 11, 2024. doi: 10.1002/ar.25379

Source: www.sci.news

Spain Unveils New Prehistoric Species of Cat

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Paleontologists from the CSIC National Museum of Natural History have identified a new genus and species of medium-sized cat from a partial jaw found in the urban area of ​​Madrid, Spain.

Mandible, skull, masticatory muscles, and life-like reconstruction Mageliferis Pegnai. Image credit: Jesus Gamarra.

A new breed of cat, its name is Mageliferis Pegnai lived in what is now Spain about 15.5 million years ago (mid Miocene).

belonged to felineThey have a bony hyoid bone, which allows them to purr, but not to roar.

“Mageliferis Pegnai It is a sister group of a clade consisting of. Pristiferis atticaextant species of the genus Ferris (like Feliz Margarita, felis sylvestrisand Felice Ribica), Proferis Aurataand Lynx” said the lead author. Dr. Manuel Salesa and colleagues at the National Museum of Natural Science, CSIC.

Fossilized remains are Mageliferis Pegnai They were discovered in 2007 at Principe Pio-2, a recently discovered fossil locality located in the urban limits of the city of Madrid, Spain.

The specimen is very well preserved, showing a complete hemimandible and all teeth except the incisors.

It is very complete and in very good preservation, providing very interesting information for making paleoecological inferences about this new feline.

“We recovered a nearly complete jaw with almost all teeth preserved in exceptional condition,” Dr. Siliceo said.

“What was most surprising was that underneath it was a small second molar, a tooth that does not exist in all modern and fossil cats. pro airlus”

Estimated weight is Mageliferis Pegnai It weighs 7.61 kg, which falls within the female weight range. Lynx Rufus, Reptile Lus Servaland caracal caracal.

“Compared to modern cats, the half-jaw of cats is Mageliferis Pegnai Principe's Pío-2 is felis sylvestrisindicates a similar size. caracal caracal, Reptile Lus Servaland Lynx'' said the paleontologists.

“Nevertheless, if we show the mandibles of these species with the same mandibular length for ease of comparison, the dentition of the new species is clearly smaller than that of the latter species, giving the specimen a more robust appearance; Has a relatively robust appearance; high mandibular body very similar to larger mandibular body Lynx”

According to the authors, Mageliferis Pegnai It is thought that they were able to generate a powerful bite force when hunting, which allowed them to kill relatively large prey.

“The Principe pio-2 feline may have preyed on relatively larger prey than other extant felines of similar size,” the researchers said.

their paper this month, Journal of Vertebrate Paleontology.

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Manuel J. Salesa other. Unraveling the diversity of early cats: A new genus of cats (Carnivora, Felidae) from the mid-Miocene of Madrid (Spain). Journal of Vertebrate Paleontology, published online on January 9, 2024. doi: 10.1080/02724634.2023.2288924

Source: www.sci.news

Robot explores deep sea to discover new species with dodecahedral design

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Robot dodecahedron mounted on a submersible (circled area)

brennan phillips

The robotic dodecahedron can capture fragile deep-sea animals, collect tissue samples, and build three-dimensional scans of the creatures, potentially speeding up the cataloging of deep-sea life. Up to 66% of marine species are still unknown to science.

brennan phillips RAD2 Sampler and colleagues at the University of Rhode Island have developed the RAD2 Sampler, which is designed to be mounted on any submersible to collect fresh tissue samples in situ from living animals. They hope this will reveal more about the creature than existing techniques, which are typically exposed to stress when pulled up from the depths.

RAD2 is a dodecahedron with an internal volume large enough to hold a basketball. It can be folded and unfolded on command to temporarily capture organisms for detailed examination and take small tissue samples that are stored directly on board the submarine for later genetic analysis. It is designed to.

The ultimate goal is to take a small biopsy and release the animal relatively unscathed, but RAD2's current technique (called tissue cutting) is “a little more crude,” Phillips said.

RAD2 has already been tested on two expeditions, collecting up to 14 tissue samples a day at a depth of around 1200 meters. “We could get small pieces of tissue, and sometimes we could get whole animals,” he says. “It depended on how big it was. So I can't say we've been able to release the animal unharmed after that, but we're moving towards that.”

The robot sampler is also equipped with a 4K resolution video camera to capture high-quality footage of the animal in motion, and a virtual model of the animal is constructed by various 3D scanning devices. In the future, Phillips said, he might be able to put sensors on each of his 12 sides of the dodecahedron and take different measurements of living things at once.

Phillips called other sampling methods “outdated” and said they essentially require people to manually put things into jars for later analysis, or use submersibles to do the same thing. Masu.

Preservation at the point of collection using RAD2 improves the quality of tissue samples and also allows researchers to detect which genes are expressed, further informing animal behavior and physiology. Phillips said it could shed some light. “This is a luxury item,” he says. “This is the best you can get with this animal, better than anyone we’ve ever had.”

eva stewart Researchers at the University of Southampton in the UK say that while digital data on deep-sea life can be a useful tool for research, there is no substitute for capturing and preserving entire samples.

“There are thousands of type specimens here. [at the university]” says Stewart.Some of them were collected by Swedish scientists carl linnaeusShe died in 1778 and says: Once you have the specimen, you are done. Even as our science changes, we can keep coming back to it. ”

But Stewart said underwater scans are useful for gelatinous and other delicate animals that are difficult to collect intact, and for how the creatures behave in their natural environment, rather than after being hoisted onto the deck of a boat. I agree that it may be helpful to understand.

“We've been conducting research to examine gene expression in sea cucumbers because we want to understand how sea cucumbers behave when they're stressed or affected by things like climate change,” says Stewart. he says. “But when you collect them and bring them to the surface, it's stressful. So being able to harvest tissue from them in a more natural way means you know what their natural baseline is, so they can It means we may be able to see more clearly what happens when placed in different environments.”

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Source: www.newscientist.com

Deep-sea Submersible Discovers Four New Species of Octopus

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A female octopus lays her eggs near a small rock outcrop, informally known as El Dorado Hill.

ROV Subastian/Schmidt Ocean Institute

Four new species of deep-sea octopus have been discovered in an underwater mountain range about two miles downstream in the Pacific Ocean off the coast of Costa Rica, according to the Schmidt Institute of Oceanography.

During expeditions in June and December 2023, researchers on the US nonprofit research vessel Falkor also used a remote-controlled vehicle to explore two low-temperature hydrothermal springs, two octopuses, and more. found a nursery, and one skate nursery. Subastian.

Previous research has found areas where octopuses live near low-temperature springs, but these environments have been difficult to find.

Typical 350°C hot hydrothermal vents are easy to spot thanks to smoke rising from the ocean floor. However, the cold spring's water temperature is only about 10 degrees Celsius higher than the average 2 degrees Celsius at the ocean floor, and is only visible through slight diffraction of light.

“It looks like it’s sparkling,” says expedition co-leader. Beth Orcutt at the Bigelow Marine Science Institute, another nonprofit in Maine.

Finding this subtle sign in the dark required multiple dives in different locations. “It's like walking through a forest you've never been in before with a flashlight looking for hot springs,” Orcutt said. “We were kind of making a bet.”

The four new species have not yet been officially described, but one has been named the dorado octopus, after the rock where it was discovered, known as El Dorado Hill.some kind of Muusocopsfemales gather to incubate eggs in warm water.

Orcutt said researchers believe the other species are new based on their appearance. They appear to be solitary, which is common among deep-sea octopuses. “They don't like having their neighbors close,” she says.

These insights into Costa Rica's unique biodiversity could inform regional conservation policy. “It is difficult [protect deep-sea wildlife] That’s when you don’t know it’s underground,” Orcutt says.

Undersea octopus farm

ROV Subastian/Schmidt Ocean Institute

These missions also help inspire and develop local scientific talent through training for early career researchers on how to lead deep-sea explorations, she says. The 310 specimens collected, which also include starfish, spider stars and sea cucumbers, will be kept at the Zoological Museum at the University of Costa Rica, rather than in the United States, where they are not easily accessible to local researchers.

More exploration is needed because the deep sea faces many threats, including mining, Orcutt said. “We're just scratching the surface.”

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Source: www.newscientist.com

Discovery of new Tyrannosaurus species through early fossil findings

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Artist's impression of Tyrannosaurus macraensis, a relative of Tyrannosaurus rex

sergei krasinski

A portion of a dinosaur skull discovered 40 years ago has been identified as a new species of dinosaur. tyrannosaurusand is probably the closest relative tyrannosaurus rex. The study adds a new twist to the long-standing debate about how many different tyrannosaurus species there were, and could help shed light on how the iconic predator evolved.

tyrannosaurus They first appeared in North America about 68 million years ago, 2 million years before the mass extinction event that wiped out most dinosaurs. Paleontologists are puzzled about the origins of this carnivore. Some suggest that it is an ancestor of tyrannosaurus Some people walked across land bridges from prehistoric Asia, while others traced their origins to southern North America.

Anthony Fiorillo Researchers from the New Mexico Museum of Natural History and Science reviewed fossils in the museum's collection that were discovered in a rock formation known as the McRae Formation in western New Mexico.

Skulls were originally classified as: tyrannosaurus, Fiorillo and his colleagues noticed differences in the bones.They proposed that this specimen represented an older species, which they named Tyrannosaurus macraiensis in reference to the rock in which it was found.

They estimated that the dinosaur was about 12 meters long, comparable in size to an aosaurus. Tyrannosaurus, However, it lived about 4 million years ago.

difference between tyrannosaurus and T. macraensis It would have been relatively subtle.on the other hand tyrannosaurus He had a prominent ridge on his eyebrow, and a bone-crushingly wide jaw with the same ridge. T. macraensis The body is less developed and the skull is thinner, Fiorillo said.

Jawbone identified as new species of Tyrannosaurus

nick longrich

Other recent studies have proposed that several species exist. tyrannosaurus And the so-called tyrannosaurus Fossils need to be reallocated. However, such proposals are controversial and are mostly rejected by dinosaur paleontologists. The new study is likely to spark further debate about that number. tyrannosaurus The species was found in North America.

“I hesitate to consider Tyrannosaurus macraiensis as different from tyrannosaurus rex” Jared Voris at the University of Calgary, Canada. He points out that many of the anatomical features that make the new species unique are also present in the specimen. tyrannosaurus.

Regardless of species assignment, the existence of such large tyrannosaurs millions of years ago is tyrannosaurus This suggests that southwestern North America was an important center of dinosaur evolution. “The age range of the proposed specimen is unique and requires further study,” Voris said. That's because it could outline a clearer picture of dinosaur evolution during the last few million years of the Cretaceous.

The New Mexico tyrannosaurus was discovered in the same rock as a giant horned dinosaur, an anthropomorphic duck-billed dinosaur, and a long-necked herbivore up to 30 meters long. Fiorillo and his colleagues tyrannosaurus It may have evolved to its gigantic size to prey on these large herbivores, and later spread north as the last “tyrant lizard” to stalk the planet.

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Source: www.newscientist.com

Argentina Unearths New Species of Sauropod Dinosaur

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Paleontologists in Argentina have discovered fossil fragments of a new genus and species of Lebatisaurus, a sauropod dinosaur that walked the earth more than 90 million years ago.

Artist's impression Sidersaura Marae. Image credit: Gabriel Díaz Yanten.

The newly discovered dinosaur lived in what is now Argentina during the Cenomanian period of the late Cretaceous period, 96 to 93 million years ago.

with scientific name Sidersaura Maraethe ancient beast had a body length of 20 meters, an estimated mass of 15 tons, and a very long tail.

The animal belongs to Rebatisauridaea large family of sauropod dinosaurs known from fragmentary fossil remains in South America, Africa, North America, Europe, and Asia.

These dinosaurs are distinguished from other sauropods by their unique teeth. Some species had tooth batteries similar to hadrosaurid and ceratopsian dinosaurs.

“Rebachisaurs were extremely important dinosaurs in the Cretaceous ecosystem, and disappeared due to an extinction event that occurred in the middle of this period. was held 90 million years ago.'' Dr. Lucas Nicolas Lersopaleontologists and colleagues from Azara Foundation Maimonides University and CONICET.

“Sidersaura Marae is one of the last rebatisaurids, but it also belongs to an evolutionary ancient lineage. ”

“This suggests that these were the largest of their group, given that some of the earliest rebachisaurs survived to the end of their lifespans, and can reach nearly 20 meters in length. It shows that.”

Sidersaura Marae fossil.Image credit: Lerzo other., doi: 10.1080/08912963.2023.2297914.

Fossilized bones are Sidersaura Marae It was discovered in the rocks of the Finkle Formation in the province of Neuquén, Patagonia, Argentina.

“The remains found include a partially articulated tail with sacral vertebrae, hind leg bones, part of the skull, and a tail vertebrae,” Dr Lerzo said.

“Having several anatomically overlapping specimens allowed us to relate them and better understand the characteristics of this new sauropod dinosaur.”

According to the team, one of the distinguishing features is: Sidersaura Marae The difference from other dinosaurs is the star-shaped shape of the hemal arch (coccyx).

Additionally, its skull is sturdy, unlike other closely related species.

“Another feature of the cranium that distinguishes it from others Sidersaura Marae “What differentiates it from other rebatisaurids is the frontoparietal foramen, which is essentially a hole in the roof of the skull,” the paleontologists said.

“This characteristic brings us closer to the following state. dicraeosaursA family of sauropod dinosaurs known for having spines on their necks and backs. ”

“The presence of early species in the Cenomanian-Turonian period, very close to the group's extinction, suggests that the evolutionary history of rebbatisaurids was more complex than previously thought.” the researchers concluded.

their paper It was published in the magazine historical biology.

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Lucas Nicolas Lerso other. The last oldie: Late Cretaceous (Cenomanian-Turonian) early basal rebachisaurids (sauropods, Diplodocoidea) of Patagonia, Argentina. historical biology, published online on January 3, 2024. doi: 10.1080/08912963.2023.2297914

Source: www.sci.news

Paleontologists identify Nanotyrannus as a distinct and small tyrannosaurus species

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Tyrannosaurus is one of the most intensively studied and best known dinosaurs. Nevertheless, their relationship and system are highly controversial. The ongoing discussion is Nanotyrannus lansensisinterpreted as either a separate genus of small-bodied tyrannosaurs, or a juvenile tyrannosaurus. tyrannosaurus rex. In a new study, paleontologists from the University of Bath and the University of Chicago examined multiple lines of evidence that Nanotyrannus lansensis as a separate species.

Nanotyrannus attack a boy tyrannosaurus. Image credit: Raul Martin.

first skull Nanotyrannus It was discovered in Montana in 1942, but paleontologists have debated for decades whether it was a separate species or just a juvenile of a much larger species. tyrannosaurus.

In the new study, paleontologist Nick Longlich of the University of Bath and paleontologist Evan Saitta of the University of Chicago reanalyzed the fossil and looked at its growth rings and body structure. Nanotyrannusand hitherto unrecognized fossils of youth tyrannosaurus.

Measuring tree rings Nanotyrannus They found that the bone was more densely packed toward the outside, indicating that bone growth was slowing down. That suggests these animals were nearly life-sized. It is not a young body that grows quickly.

Fossil growth modeling shows that the animal could have weighed between 900 and 1,500 kg and reached a maximum length of 5 meters, about 15% of the size of a giant. . tyrannosaurus8,000 kg and grew to over 9 m.

“I was quite surprised when I saw these results. I didn't expect to see such conclusive results,” said Dr. Longlich.

“If they were young tyrannosaurus They're supposed to grow like crazy and gain hundreds of pounds a year, but we don't see it that way. ”

“We tried modeling the data in different ways, but still got low growth rates. This seems to put an end to the hypothesis that these animals are young.” tyrannosaurus”

Researchers found no fossil evidence that combined both traits to support the existence of different species Nanotyrannus and tyrannosaurus —If one turns into the other, it will exist.

Every fossil they examined could be confidently identified as one or the other species.

The growth patterns of other tyrannosaurs were also inconsistent with the hypothesis that these tyrannosaurs were young. tyrannosaurus.

“If you look at other juvenile tyrannosaurs, you'll see a lot of characteristics that are typical of adults. Very young. tarbosaurus — next of kin of tyrannosaurus — exhibiting unique characteristics of adults,” Dr. Longrich said.

“Just as kittens look like cats and puppies look like dogs, the various juvenile tyrannosaurs are also unique. And Nanotyrannus nothing similar tyrannosaurus”

“It may have grown in a completely different way than other tyrannosaurs or other dinosaurs, but it's more likely that it simply wasn't a dinosaur. tyrannosaurus”

But it poses a mystery. Nanotyrannus not a boy tyrannosaurusSo why didn't anyone find the young man? tyrannosaurus?

“That was always one of the big questions. Well, it turns out we actually found it,” Dr. Longrich said.

“However, this fossil was collected many years ago, put away in a box of unidentified bones in a museum drawer, and then forgotten.”

Nanotyrannus They were lighter in build and had longer limbs than their stouter relatives. It also had larger arms, unlike those known for their short arms. tyrannosaurus.

“Actually, my arms are longer than people's.” tyrannosaurus.Even the biggest one tyrannosaurushave shorter arms and smaller claws than these smaller animals. Nanotyrannus. This was an animal whose arms were actually pretty scary weapons. It's actually a completely different animal, smaller, faster and more agile,” Dr. Longrich said.

“tyrannosaurus While animals relied on size and strength, this animal relied on speed. ”

“The long arms and other features suggest it was only a distant relative.” tyrannosaurus — and may have been sitting outside the family TyrannosauridaeWhich tyrannosaurus Part of the predatory dinosaur family. ”

a paper The survey results were published in a magazine fossil research.

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Nicholas R. Longrich and Evan T. Saitta. 2024. Taxonomic status of Nanotyrannus lansensis (Dinosaur: Tyrannosauridae) – A different taxon of small tyrannosaurs. Phos.stud 2 (1): 1-65; doi: 10.3390/fossils2010001

Source: www.sci.news

Controversy Surrounds Identification of Tiny Tyrannosaur Fossil as Potentially Another Species

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Illustration of Nanotyrannus fighting a young Tyrannosaurus Rex

raul martin

tyrannosaurus rex After all, it may not have been the only large carnivore that ruled North America during the Late Cretaceous. Reinterpretation of some fossils of small dinosaurs sometimes classified as young dinosaurs tyrannosaurus This adds weight to the controversial idea that it is a separate small species called . Nanotyrannus lansensislived with the dinosaur king.

“This is the most famous fossil animal in the world,” he says Nicholas Longrich At the University of Bath, UK. “A lot of people are watching. And we can't agree.”

This debate has divided paleontologists for decades. A paper from the 1960s revealed that a skull excavated 20 years earlier in the Hell Creek Formation in Montana was tyrannosaurus that died before reaching full maturity. However, in the 1980s, others argued that the differences between the skull and known skulls were: tyrannosaurus The specimen showed that this fossil was actually an adult of another species, and they named it Nanotyrannus lansensis.

Recent studies based on additional fossils dispute this, arguing that the differences between miniature and full-sized fossils are: tyrannosaurus The fossils were not of different species, but of different times. This discussion has implications for understanding the ecology and diversity of dinosaurs in the period just before their extinction.

Now, with Longrich Evan Saitta Researchers at the University of Chicago have compiled six pieces of evidence that support identifying the smaller fossils as: Nanotyrannus. This includes cataloging more than 150 individual features that differ between the fossil in question and the known fossils. tyrannosaurus Fossils include things like a narrower snout and smoother teeth. They argue that all this cannot change between boys and adults. tyrannosaurus.

The researchers also analyzed the patterns of bone growth rings, which form when bones stop growing each year. As the animal grows slower, the distance between the growth rings decreases. Researchers say they found these rings to be tightened, suggesting that the smaller fossils represent young adults. Nanotyrannus Rather than a boy tyrannosaurus They rate these adults Nanotyrannus Their weight would be between 1,000 kg and 2,000 kg, equivalent to a quarter of an adult. tyrannosaurus 8000 kg. “No matter how you graph the data, you can’t turn it into an animal. tyrannosaurus” Longrich says.

The latest evidence is a fossilized frontal bone (located between the eye and skull) that Longrich unearthed from the archives of the University of California Museum of Paleontology, which researchers interpret as a juvenile fossil. tyrannosaurus Because it is definitely different from the hypothesis, Nanotyrannus fossil. “It's an animal smaller than a human.” Nanotyrannus But it is tyrannosaurus Morphology,” Longrich says.

Some outside researchers say they remain unsure that the tiny fossil is actually a separate species. “No problem Nanotyrannus If science proves it, it’s real.” holly woodward At Oklahoma State University written Juvenile species were identified in a tree ring survey conducted in 2020. tyrannosaurus explanation. “We’re not convinced that their interpretation is any more accurate than ours,” she said, adding that the fully grown animal specimens were “unusual.” Nanotyrannus It will be necessary to resolve different interpretations.

thomas carr A professor at Carthage College in Wisconsin has long argued that the fossil is a juvenile. tyrannosaurus, adding that the front bone found at Berkeley was too incomplete to sway him. “I don’t take this seriously at all,” he says.

scott parsons Professors at the College of Charleston in South Carolina are more welcoming of what he says is a new perspective on a long-stalled rift among paleontologists. “This new paper doesn’t settle this debate, but I’m optimistic that it will be a game-changer,” he says.

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Source: www.newscientist.com

Confirmation of a new species of plesiosaur found in the United States

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Paleontologists have described a new genus and species of small polycotyledonous plesiosaur from two specimens discovered in the US states of Wyoming and South Dakota.

rebuilding the life of Untahira Specta The proposed habitat is a sunlit body of water just below the earth's surface, and the eyes are covered by bulges above the orbits.Image credit: Clark other., doi: 10.1016/j.cretres.2023.105812.

Untahira Specta lived in the waters of Western Inland Sea Route Late Cretaceous period, approximately 80.5 million years ago.

This marine reptile is polycotyledonous plantsa family of plesiosaurs that evolved in the Early Cretaceous and radiated into multiple genera in the Late Cretaceous.

“Polycotyledons were a marine herpeta superfamily of the Cretaceous period. plesiosaurinae” said the lead author. Dr. Robert Clark and colleagues at Marshall University.

“The earliest polysperms are known from the Aptians of Australia, but they reached North America by the Albians and achieved an international distribution before dying out along with the rest of the polysperms. plesiosaur At the end of the Maastrichtian. ”

“Polysosaurs had short tails, limbs transformed into large paddles, and plesiosaur-like bowplans of broad, hydrodynamic bodies with extended pectoral and pelvic girdle, but short It also had a derivative condition: a large head with a neck and an elongated snout.”

“It has converged, but Pliosauridae In these traits, the small clefts and teeth of most polycots indicate that they occupied different ecological niches. ”

holotype of Untahira Specta.Image credit: Clark other., doi: 10.1016/j.cretres.2023.105812.

Two fossilized skulls (holotype and paratype) Untahira Specta Recovered from the Baculites obtusus zone of the Sharon Springs Formation in the United States.

“The holotype is a skull and mandible with an almost complete cervical, sacral, caudal series, partial dorsal series, ribs, part of the pelvic and pectoral girdle, both iliac bones, both anterior paddles, both It has a rear paddle,” the paleontologists said. Said.

“The paratype is a complete cranium, a three-part lower jaw, and five small, fragmentary, unidentified postcranial elements.”

Untahira Specta It was a small polycotyledonous plant, 2.3–2.6 m (7.5–8.5 ft) long, with a broad skull and distinctive paddle.

The large eyes had flat protuberances that probably blocked sunlight. It is possible that they were visually chasing prey just below the water surface.

“Comparisons with extant quadrupeds suggest several characteristics of quadrupeds. Untahira Specta “This may be an adaptation to predation by visual tracking in sunny environments, an interpretation with ecological implications for other aquatic reptiles,” the researchers said.

their findings It was published in the magazine Cretaceous research.

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Robert O. Clark other.Elucidation of a new genus of small polycotyledonous plesiosaurs that lived in the Upper Cretaceous of the Western Interior Seaway and its genus doricorinchops. Cretaceous research, published online on December 24, 2023. doi: 10.1016/j.cretres.2023.105812

Source: www.sci.news

A new species of toad has been found living in African volcanoes

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Scientists have identified a new genus and species of true toad from a single specimen found in a high-altitude forest. mount kenya, an extinct volcano in Kenya and the second highest mountain in Africa after Kilimanjaro. Contrary to the popular belief that most of Kenya’s amphibians arose after volcanic activity subsided millions of years ago, this new species is related to the Kenya volcanic toad (Kenya Phrynoides vulcanis) – Its origins may date back as far as 20 million years, making it considerably older than the volcanic formation of Mt Kenya itself.

artistic performance Kenya Phrynoides vulcanis (A), dorsal view of the left hand of the holotype (B), and photographs of the dorsal (C) and ventral (D) sides of the holotype before preservation. Image credit: Liedtke other., doi: 10.1093/zoolinnean/zlad160.

Dr Simon Loader, lead curator of vertebrates at the Natural History Museum, London, said: ‘Many of Kenya’s mountains are volcanic or geologically relatively new, so discovering ancient lineages that have lasted for millions of years is unlikely. It’s amazing.”

“It’s a real challenge to figure out how it got here.”

“We can’t say for sure, but it seems likely that they were once more widespread, and as the climate has changed over the past tens of millions of years, they have tracked their way through tropical forests, with their final destinations being the mountaintops. It was ‘Mt Kenya’. ”

The discovery of Kenya’s volcanic toads calls into question the concept of the Kenya interval, a term used to describe the striking contrast in amphibian diversity between Kenya and its neighboring countries.

Ethiopia and Tanzania have long been hotspots for amphibian biodiversity, but Kenya’s geological history and frequency of tectonic activity make it a difficult place for these organisms to thrive.

unique features Kenya Phrynoides vulcanis This suggests that the Kenyan Interval may not be as simple as previously believed.

When this toad was first discovered in Mount Kenya’s pit in 2015, it already seemed very different from the species normally seen in the area.

“We were really surprised to see this animal. It looked nothing like anything we had seen before, but it was similar to what we know and call the Tanzanian animal. Ta” Churamiti MaridadiIt is a forest tree toad that lives in the Ukaguru Mountains rainforest,” said National Museums of Kenya curators Dr Patrick Maronza and Dr Victor Wasonga.

Kenya Phrynoides vulcanisDistinctive features include its small size, more frog-like body, and distinctive green and brown markings.

Genetic and morphological differences from other known toad species have led to its recognition at the genus level.

Clues from physical features such as enlarged fingertips suggest it may be a climber.

Its thumb has a sharp tip known as a nuptial spine found in many male frogs and toads, which helps the male grasp the female and encourage reproduction.

“The forest toad found in the mountains of East Africa is unusual and does not resemble typical toads,” said Dr. Hendrik Müller, a researcher at Martin Luther University Halle-Wittenberg.

“More interestingly, some individuals are known to have an unusual reproductive strategy called ovoviviparity.”

“In ovoviviparity, the eggs hatch inside the female’s body. This means that the chicks are born from the mother as small toads, rather than as tadpoles.”

This finding is reported in the following article: paper inside Zoological journal of the Linnean Society.

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H. Christoph Liedtke other. A new species of toad discovered from Mount Kenya sheds light on the biogeography of East Africa’s mountains. Zoological journal of the Linnean Society, published online on November 7, 2023. doi: 10.1093/zoolinnean/zlad160

Source: www.sci.news

Researchers identify unique species of seal in the Arctic

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This scientific study used satellite transmitters, population counts, and DNA analysis of tissue samples to describe the special Kangi ringed seal in the Ilulissat Icefjord. Here, a satellite transmitter is attached to the seal’s back.Credit: Pinngortitaleriffik – Greenland Institute of Nature Research

Local hunters in the Icefjord near Ilulissat are familiar with a special type of ringed seal known as the Kangia seal. Kangia seals vary in size and appearance, being significantly larger than the common Arctic ringed seal, and with markedly different fur colors and patterns. Recent scientific research has revealed that this distinctive seal has been genetically separated from Arctic seals over a long period of over 100,000 years.

Exploring the natural wonders of the Arctic can be difficult. Extreme weather and vast distances often hinder researchers’ quest to uncover nature’s mysteries.

However, a research project led by Greenlandic and Danish researchers has succeeded in describing a new species of ringed seal that lives in an ice fjord near Ilulissat in West Greenland. A unique natural area on the UNESCO World Heritage List.

The results were recently published in a prestigious scientific journal. molecular ecology.

Kangia ringed seals are larger than the typical Arctic ringed seal, and their fur is a different color and has more distinctive markings.Credit: Pinngortitaleriffik – Greenland Institute of Nature Research

small population

For years, researchers worked with local hunters to trap seals in nets and attach small satellite transmitters to their backs. As the seals flew, satellite transmitters sent messages about the seal’s location.

“We found that the Kangia seals mainly stayed within the ice fjords. We were able to count the seals from the plane, so we estimated that there was only about one seal. There are 3,000 special Kangi ringed seals,” said Akual Rosing Asvid, a senior researcher at the Greenland Institute for Nature Research Pingoltitalerifik and one of the researchers who supported the study. .

Color and pattern of the fur of the Kangia ringed seal (left) and a typical Arctic ringed seal (right).Credit: Pinngortitaleriffik – Greenland Institute of Nature Research

Their small population is very unusual compared to the typical Arctic ringed seal, which is huge and often travels thousands of kilometers around the North Pole in search of food.

isolated for thousands of years

The researchers also took small tissue samples from the captive seals. The samples were sent for genetic analysis to determine the seal’s identity. DNA The results revealed that Kangia ringed seals are genetically distinct from typical Arctic ringed seals.

Kangia ringed seals live in the Ilulissat Icefjord, which is a UNESCO World Heritage Site due to its spectacular and unique nature.Credit: Pinngortitaleriffik – Greenland Institute of Nature Research

However, where and how the Kangia ringed seal became isolated from other Arctic ringed seals and why it acquired new special biological characteristics remains a mystery.

Perhaps other arctic fjords also have special seals

The study highlights that there is still much we don’t know about the biodiversity of the Arctic and its potential to adapt to climate change and human activities.

“There are many other fjords in the Arctic that have not yet been studied in detail, and ringed seals may also carry new genetic mutations in these areas,” said Rune Dietz, professor at Aarhus University’s School of Ecological Sciences. Point out. he participated in the research.

Reference: “Evolutionarily distinct ringed seals of the Ilulissat Icefjord” Aqqalu Rosing-Asvid, Ari Löytynoja, Paolo Momigliano, Rikke Guldborg Hansen, Camilla Hjorth Scharff-Olsen, Mia Valtonen, Juhana Kammonen, Rune Dietz, Frank Farsø Rigét, Steve By H Ferguson, Christian Leidersen, Kit M. Kovacs, David M. Holland, Jukka Jarnvall, Petri Auvinen, Morten Tange Olsen, October 19, 2023. molecular ecology.

DOI: 10.1111/mec.17163

Source: scitechdaily.com