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New species of bizarre, bipedal, toothless crocodile relative from the Triassic discovered in Ghost Ranch

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Unearthed in Ghost Ranch, New Mexico, Labrujasuchus expectatus—the ‘Witch Croc’—highlights the weirdness of life at the dawn of the dinosaurs and the legacy and ongoing discoveries at an iconic site 20 years into excavation

In the Triassic, the modern animals we know were just beginning to diversify into a menagerie of forms and body plans that rhyme with the lifestyles of extinct and living animals better known to the public, but nested in groups that ended up taking wildly divergent paths. Case in point: Labrujasuchus expectatus.

Described in the journal Journal of Vertebrate Paleontology, Labrujasuchus looked very much like ornithomimosaurs, a group of bipedal dinosaurs from the Cretaceous with body plans similar to those of modern ostriches. But Labrujasuchus comes from the branch of archosaurs that led to crocodiles, famously four-legged and full of teeth. The newly-described Labrujasuchus navigated the world on two legs with tiny arms and a toothless mouth tipped in a beak—about as far away from a crocodile as possible.

In the Triassic, you can expect the unexpected. 

The Triassic was the first period of the Mesozoic Era — often called the “Age of Dinosaurs.” It lasted from about 252 million to 201 million years ago, after the massive Permian extinction that wiped out most life on Earth.

Among the primordial Star Wars bar denizens of the epoch were the lagerpetids, bipedal dinosaur cousins whose relatives would take to the skies as pterosaurs; the funky tree-dwelling Drepanosaurus, with a single tree-sloth-like claw on its hands and a little one on its prehensile tail; and the aquatic reptilian mini-tank, Vancleavea, to name a few. Labrujasuchus expectatus, the newest identified member of Shuvosauridae—a group of ancient crocodile relatives with body plans resembling bipedal, small-armed theropod dinosaurs—stepped into this world of bizarre reptiles with both feet.

“We see a lot of the successful strategies for modern animals and non-avian dinosaurs first arise in the Triassic, and shuvosaurs are a great example of that convergent evolution,” says Dr. Alan Turner, lead author on the paper. “Bipedalism is certainly a unique path for crocodile relatives to take, but it’s a path well-trod by dinosaurs and later birds. It obviously worked for these animals.”

One of only five identified species, Labrujasuchus expectatus fills the gap between two earlier discovered shuvosaurs from the region, an evolutionary link paleontologists knew was waiting to be found. The discovery was the expected unexpected, which inspired the species name ‘expactatus’. The witchy genus moniker, Labrujasuchus, references the ‘Ranchos de los Brujos,’ or Ranch of the Witches, an old Spanish name for Ghost Ranch, and the Greek word Σοῦχος (suchus) meaning “crocodile”.

“Legend has it, the local rancheros gave the site the name ‘Ranchos de Los Brujos’ to keep folks away from the cattle-rustling operations of the Archuleta brothers,” says Dr. Nate Smith, co-author and Gretchen Augustyn Director & Curator of the NHMLAC Dinosaur Institute. “We wanted to give a nod to that colorful history, and honor the incredible role Ghost Ranch has played in expanding our view of the Triassic. We also wanted to highlight how the fossil record works—finding one shuvosaur from earlier in the Triassic and one from later meant that we paleontologists knew there were probably more from in-between waiting to be discovered and described.”

(Ghost Ranch is a famous desert retreat, fossil site, and cultural landmark in northern New Mexico)

Marking 20 Years of Collaboration at Ghost Ranch

With its bizarre assortment of creatures, the Triassic can feel like it belongs to another Earth entirely, but the body plans of long-gone weirdos reverberate through time, mirroring our modern weirdos, who are often in danger of going extinct. In short, understanding the Triassic past helps us better understand and protect our present, and perhaps nowhere on Earth gives a better view of that long-gone epoch than Ghost Ranch. Home to four quarries excavated by paleontologists for decades, Ghost Ranch continues to produce some of the most exquisitely produced fossils from the epoch.

 

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‘Nagatitan’: Southeast Asia’s biggest long-necked dinosaur discovered

New dinosaur Mbiresaurus, a boon for Zimbabwe and Virginia Tech paleontology

 

‘Nagatitan’: Southeast Asia’s biggest long-necked dinosaur discovered

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A new type of long-necked plant-eating dinosaur – the largest ever found in Southeast Asia – has been revealed in a study led by researchers at University College London (UCL), Mahasarakham University, Suranaree University of Technology and Sirindhorn Museum in Thailand.

The dinosaur, described in a new paper in the journal Scientific Reports, was identified from bones found at the edge of a pond in north-eastern Thailand 10 years ago.

Analysing spine, rib, pelvis and leg bones, including a front leg bone 1.78 metres long (as long as a human), the research team estimated that the dinosaur would have weighed 27 tonnes – about the same as nine adult Asian elephants – and measured 27 metres in length.

It has been named Nagatitan chaiyaphumensis, with “Naga” referring to a mythological aquatic serpent in Thai and Southeast Asian folklore, “Titan” referring to the giants of Greek mythology and chaiyaphumensis meaning “from Chaiyaphum”, the Thai province where the fossils were discovered. It is the 14th dinosaur to be named in Thailand.

It belonged to the sauropod family of dinosaurs – long-necked, long-tailed plant-eaters that included the Diplodocus and Brontosaurus – and lived in the Early Cretaceous period between 100 and 120 million years ago.

Lead author Thitiwoot (Perth) Sethapanichsakul, a Thai PhD student at UCL Earth Sciences, said: “Our dinosaur is big by most people’s standards – it likely weighed at least 10 tonnes more than Dippy the Diplodocus (Diplodocus carnegii). However, it is still dwarfed by sauropods like Patagotitan (60 tonnes) or Ruyangosaurus (50 tonnes).

“We refer to Nagatitan as ‘the last titan’ of Thailand. That is because it was discovered in Thailand’s youngest dinosaur-bearing rock formation. Younger rocks laid down towards the end of the time of the dinosaurs are unlikely to contain dinosaur remains because the region by then had become a shallow sea. So this may be the last or most recent large sauropod we will find in Southeast Asia.”

During the Early Cretaceous the environment would have been arid to semi-arid – a preferred habitat for sauropods who appeared to thrive in these environments, relying on the surface area of their long necks and tails to shed heat and regulate their body temperature.

The area where the specimens were found also appeared to be part of a meandering river system, which would have been home to fish, freshwater sharks and crocodiles.  

Nagatitan would have lived alongside smaller plant-eating dinosaurs such as iguanodontians and early branching ceratopsians (cousins of the Triceratops), as well as big meat-eaters including carcharodontosaurians and spinosaurids, and flying reptiles called pterosaurs eating fish from the river.

Nagatitan was a somphospondylan sauropod – a subgroup of sauropod that became widespread about 120 million years ago. The authors found that it specifically belonged to a narrower group within the somphospondylans called Euhelopodidae, which represents a group of somphospondylan sauropods only found in Asia.

Nagatitan is distinct from other species due to a combination of unique features on its spine, pelvis and legs. A life-size reconstruction of the dinosaur is on display at the Thainosaur Museum at Asiatique in Bangkok.

Sethapanichsakul said: “My dream is to continue pushing to get Southeast Asian dinosaurs recognised internationally. More international collaborations between Thailand and other institutions like UCL can further our understanding of the region’s palaeobiology and apply it to a global context. This all starts with identifying and describing the specimens we have found first. We have a large collection of sauropod fossils that have not yet been formally described – these may include a number of new species.

“I’ve always been a dinosaur kid. This study doesn’t just establish a new species but also fulfils a childhood promise of naming a dinosaur.”

Co-author Professor Paul Upchurch, based at UCL Earth Sciences, said: “This discovery comes out of a new collaboration between UCL and colleagues in Thailand. The material was studied both in Thailand and at UCL – 3D scanning and printing has meant that we can study the specimen and collect data without having to travel (good for reducing carbon footprint).

“We have had a long-standing interest in the evolution of these gigantic plant eaters and have good collaborative links with researchers around the world. It is great to work with Thai colleagues and start to get insights into what was happening in Southeast Asia during the Jurassic and Cretaceous.”

A team of five academics work on different aspects of dinosaur evolution at UCL, with strong collaborative links to the Natural History Museum. The extended research group comprises four research fellows and postdoc researchers, and more than 10 PhD students. At least four of the PhD students are working on dinosaur evolution, with the others looking at a wider array of other evolutionary questions relating to vertebrates, including crocodiles and birds.

Project leader and National Geographic Explorer Dr Sita Manitkoon, researcher at the Palaeontological Research and Education Centre, Mahasarakham University said: “Although Thailand is a small country within Asia, we have a very high diversity in dinosaur fossils, possibly the third most abundant in Asia in terms of dinosaur remains. We’ve only really been studying dinosaurs in Thailand about 40 years (since the first dinosaur was named in 1986), and already we have a surge of younger generation palaeontologists, who are actively undertaking research and promoting palaeontology and its importance within the country.”

 

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Fossils reveal dinosaurs of prehistoric Patagonia

Discovery of Mbiresaurus gives birth to new theory on dinosaurs in Supercontinent Pangea

New dinosaur Mbiresaurus, a boon for Zimbabwe and Virginia Tech paleontology

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The unearthing of one of the earliest dinosaurs ever found is a major win for the Natural History Museum of Zimbabwe.

The Mbiresaurus skeleton is almost complete, making it a perfect reference material for further finds. It is also the first sauropodomorph find of its size from Zimbabwe, where most of the earlier sauropodomorph finds are usually of medium- to large-sized animals.

“The discovery of the Mbiresaurus is an exciting and special find for Zimbabwe and the entire paleontological field,” said Michel Zondo, a curator and fossil preparer at the museum.

Darlington Munyikwa, deputy executive director of the National Museums and Monuments of Zimbabwe, said: “The unfolding fossil assemblage from the Pebbly Arkose Formation in the Cabora Bassa Basin, which was hitherto known for paucity of animal fossils, is exciting. A number of fossil sites [are] waiting for future exploration were recorded, highlighting the potential of the area to add more valuable scientific material.”

Much of the Mbiresaurus specimen is being kept in Virginia Tech’s Derring Hall as the skeleton is cleaned and studied. All of the Mbiresaurus skeleton and the additional found fossils will be permanently kept at Natural History Museum of Zimbabwe in Bulawayo, Zimbabwe.

“This is such an exciting and important dinosaur find for Zimbabwe, and we have been watching the scientific process unfold with great pride,” said Moira Fitzpatrick, the museum’s director. She was not involved in the study. “It has been a pleasure to work with Dr. Griffin,and we hope the relationship will continue well into the future.”

The discovery of Mbiresaurus also marks another highpoint for the Paleobiology and Geobiology Research Group. In 2019, Nesbitt authored a paper detailing the newly named tyrannosauroid dinosaur Suskityrannus hazelae. Incredibly, Nesbitt discovered the fossil at age 16 as a high school student participating in a dig expedition in New Mexico in 1998.

“Our group seeks out equal partnerships and collaborations all over the world and this project demonstrates a highly successful and valued collaboration,” Nesbitt said. “We will continue studying the many fossils from the same areas as where the new dinosaur came from and explore the fossil beds further.”

 

Africa’s oldest known dinosaur skeleton to bridge the ‘Missing Middle’

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An international team of paleontologists led by Virginia Tech has discovered a skeleton of new long-necked dinosaur Mbiresaurus raathi, that fills a critical geographic gap in the fossil record of the oldest dinosaurs.

The skeleton, mostly intact, was first found by a graduate student in the Virginia Tech Department of Geosciences and other paleontologists during two excavations over the course of period in 2017 and 2019.

Published on Thursday in the journal Nature, the findings show that the skeleton is the oldest dinosaur skeleton ever found in Africa. The animal is estimated to have been 6 feet long with a long tail. It weighed anywhere from 20 to 65 pounds. The skeleton, missing only some of the hand and portions of the skull, was found in northern Zimbabwe.

Dinosaur

“The discovery of Mbiresaurus raathi fills in a critical geographic gap in the fossil record of the oldest dinosaurs and shows the power of hypothesis-driven fieldwork for testing predictions about the ancient past,” said Christopher Griffin, who graduated in 2020 with a Ph.D. in geosciences from the Virginia Tech College of Science.

Africa’s oldest-known definitive dinosaurs, it was roughly equivalent in age to the oldest dinosaurs found anywhere in the world. The oldest known dinosaurs — from roughly 230 million years ago, the Carnian Stage of the Late Triassic period — are extremely rare and have been recovered from northern Argentina, southern Brazil, and India.

Sterling Nesbitt, co-author of the study, said, “Early dinosaurs like Mbiresaurus raathi show that the early evolution of dinosaurs is still being written with each new find and the rise of dinosaurs was far more complicated than previously predicted.”

 

Fatal Cancer found in dinosaur that lived in present Canada 76 million years ago

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Roughly 76 million years ago, a Centrosaurus that lived in what is now Canada was walking around with a malignant tumour in its lower leg, found scientists based on its deformed fossil bone.

The cancer was diagnosed osteosarcoma and this is the first time that cancer has been confirmed in a dinosaur, although scientists have identified benign tumours in Tyrannosaurus rex fossils in the past.
Researchers say that the tumour could have eventually been fatal, but the Centrosaurus probably died in a flood with the rest of its herd.

dinosaur bone cancer / © ROYAL ONTARIO MUSEUM/MCMASTER UNIVERSITY

This deformed bone had a malignant tumor in the dinosaur fossil of partial fibula—a bone from the lower leg—belonged to a horned, plant-eating Centrosaurus that lived about 76 million years ago in what is now Dinosaur Park in southern Alberta in Canada.

Paleontologists initially thought the bone was deforemd due to a fracture but a new study, published in The Lancet Oncology, found it after comparing it with a bone tumor from a human patient. The osteosarcoma cancer primarily attacks teens and young adults and causes tumors of immature bone tissue, frequently in the long bones of the leg.

Similar cancer diagnosis in dinosaurs

In the past such a tumor was found in Tyrannosaurus rex fossils and arthritis in duck-billed hadrosaurs, as well as an osteosarcoma in a 240-million-year-old turtle but they were benign. The present study is the first to confirm a dinosaur cancer diagnosis at the cellular level.

Scientists examined the full fossil with high-resolution computerized tomography scans and examined thin sections under the microscope to find the tumor advanced enough that it had probably plagued the animal for some time.

A similar case in a human, left untreated, would be fatal, they wrote. However, because the fossil was found in a bone bed with lots of other Centrosaurus specimens, the dinosaur likely died in a flood with the rest of its herd and not from the cancer, they said.