Tag Archives: CrocodileLike

700-Million-Year-Old Fossils of Crocodile-Like Apex Predators Discovered in Argentina

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Paleontologists have unearthed exquisitely preserved skulls and jaws, along with parts of the skull and jaws belonging to a previously unidentified species of Peilosaurus in Patagonia, Argentina.

Reconstruction of Kostensuchus atrox. Image credit: Gabriel Dias Janten.

Kostensuchus atrox roamed the Earth during the Cretaceous period approximately 70 million years ago.

This ancient species was a formidable predator, measuring about 3.5 m (11.5 feet) in length and weighing around 250 kg.

These animals featured broad, powerful jaws and large teeth capable of consuming substantial prey, including medium-sized dinosaurs.

Kostensuchus atrox was a member of the Peirosauridae family of crocodiles within the sub-order Notosuchia.

“This new species belongs to the notosuchian clade Peirosauridae, representing the latest and southernmost records of this crocodile-like group,” stated Dr. Fernando Novas, a paleontologist at Argentino de Ciencias Naturales ‘Bernardino Rivadavia.

The fossilized skulls and bones of Kostensuchus atrox were discovered in the Chorrillo Formation, approximately 30 km southwest of El Calafate in the province of Santa Cruz.

“The Chorrillo Formation dates back about 70 million years,” the paleontologist explained.

“At that time, southern Patagonia boasted a warm, seasonally humid environment filled with freshwater floodplain plants, home to dinosaurs, turtles, frogs, and various mammals.”

“The newly excavated fossils from this layer are almost complete, including skulls and jaws exhibiting visible details, along with multiple bones from the body.”

Kostensuchus atrox ranks as the second-largest predator identified in the Chorrillo Formation and likely served as one of the region’s top predators.

This new species is also the first crocodile-type fossil found in this geological layer and is among the most intact examples of a crocodilian ever discovered, offering scientists unique insights into these prehistoric creatures and their environments.

“The discovery of Kostensuchus atrox significantly enhances our understanding of the anatomy of the widely distributed Peilosaurus population, which was previously known from highly fragmented specimens found in South America and Madagascar,” the researchers noted.

“The new anatomical data illuminate both the similarities and distinctions between the extensive Peirosauridae and Baurosuchidae, other crocodile-like lineages that evolved independently into apex predators during the Cretaceous period in Gondwana.”

“Kostensuchus atrox provides insights into late Cretaceous ecosystems in southern Patagonia, which formed in freshwater habitats within warm climates, supporting diverse faunas of dinosaurs, mammals, and other vertebrates in a seasonally humid environment,” they added.

“The wide and tall snout of Kostensuchus atrox, particularly its robust forelimb anatomy, along with large, sturdy teeth and broad adductor chambers in the skull, suggests this new species was capable of overpowering substantial prey.”

“These characteristics indicate that Kostensuchus atrox occupied the role of the top predator within this ultimate Cretaceous ecosystem.”

The discovery of Kostensuchus atrox is detailed in a paper published this week in the journal PLOS 1.

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Fe Novas et al. 2025. A new large carbonized crocodile from the Maastrichtian in southern Patagonia, Argentina. PLOS 1 20(8): E0328561; doi: 10.1371/journal.pone.0328561

Source: www.sci.news

Prehistoric crocodile-like reptile unearthed in Brazil’s Triassic era

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A new genus and species of Triassic gracillid reptile has been identified from fossils discovered in the Santa Maria Formation of Brazil.

Artistic representations of the Middle to Late Triassic landscape of southern Brazil: (a) large Prestosuchus chinensis It feeds on the carcasses of dicynodonts, Parvosuchus aurelioi Compete for scrap metal. (b) and (c) Parvosuchus aurelioiImage courtesy of Matheus Fernandes.

Named Parvosuchus aurelioiThe new species roamed the Earth about 237 million years ago (during the Triassic Period).

The ancient reptiles Gracilidae (Gassiliscidae), an extinct family of pseudo-nudibranchs that lived in China, Argentina, and Brazil.

“Pseudobranchs were a common group of ancient tetrapod reptiles during the Triassic, before the dominance of dinosaurs, and some of their species were among the largest carnivores of their time,” says paleontologist Rodrigo Muller of the Federal University of Santa Maria.

“Smaller pseudosuchians, known as gracilischiidae, live alongside these apex predators and have been found in areas such as China and Argentina.”

“These creatures were characterized by relatively large heads with wide mouth openings, carnivore-like teeth, slender limbs, and a quadrupedal posture.”

Partial skeleton of Parvosuchus aurelioi Found in Santa Maria Formation Paraiso do Sul, Rio Grande do Sul, Brazil.

It consists of a complete skull including the lower jaw, 11 dorsal vertebrae, a pelvis, and partially preserved limbs.

“The reptile’s skull is 14.4 centimetres long and features elongated jaws with pointed, backward-curving teeth and several skull openings,” Dr Muller said.

“The skeleton is lightweight and estimated to be less than one metre long.”

“These characteristics are Parvosuchus aurelioi This is the first time that a species of this group has been identified in Brazil.”

“This discovery highlights the diversity of Triassic pseudo-pinnids.”

Discovery Parvosuchus aurelioi It has been reported paper Published in the journal today Scientific Reports.

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R.T. Müller. 2024. A new small, predatory pseudobranchial sauropod from the Middle to Late Triassic of southern Brazil. Scientific Reports 14, 12706; doi: 10.1038/s41598-024-63313-3

Source: www.sci.news

Oldest Fossilized Crocodile-Like Skin Discovered by Scientists

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Researchers have discovered what is believed to be the oldest skin fossil on record.

The alligator-like skin, which is at least 286 million years old, was preserved in an ancient buried cave in what is now Oklahoma. The discovery could help unravel evolutionary mysteries and provide important clues to a time when some animals were transitioning to living on land.

“Finding old skin fossils like this is a great opportunity to peer into the past and learn what the skin looked like on these early animals,” said the University of Toronto graduate student and co-author of the book. says lead author Ethan Mooney. the paper said in a news release.

Three-dimensional skin casting and compacted fossil of an unknown amniote.
Mooney et al. / Current Biology

Discovery announced Thursday Published in the scientific magazine “Current Biology”, created in a quarry and cave system called Richard's Spur. Researchers believe the animals fell into the cave system and were preserved by seeping oil and tar that enveloped them.

Skin is a three-dimensional mold with fossilized tissue attached to it.

“There are very few examples of Paleozoic land animals that have preserved skin,” said Paul Olsen, a paleontologist and Columbia University professor who was not involved in the paper. “He's one of the reasons why this is so important.”

Lepospondyl, temnospondyl, and dermal scales of an unknown quadruped.
Mooney et al. / Current Biology

The preserved skin was discovered at a site full of fossils of lizard-like creatures called lizards. captorinus aguti, However, it was not clearly associated with any particular skeleton.

Olsen said the skin could help solve the mystery of how reptiles and mammals diverged from each other during evolutionary history. Her two branches of life have a common ancestor.

“They hypothesize that the common ancestor of reptiles and mammals had reptilian-like skin, but their reptilian-like skin is not associated with the skeleton, so they have We can't really show that with the materials we have,” Olsen said of the authors. “Maybe this site will reveal that in the future.”

Horny zone of Captorhinus aguti (OMNH 52541).
Mooney et al. / Current Biology

Source: www.nbcnews.com