Introducing Titanomachya gimenezi

 

Titanomachya gimenezi. Image credit: Gabriel Díaz Yantén.

Titanosaurian sauropods exhibit a remarkable body size disparity in the Late Cretaceous ecosystems of South America. Some of them, were the largest animals ever to walk the Earth. In central Patagonia, there was a coexistence of small bodied saltasauroids, aeolosaurines, and larger bodied titanosaurs of uncertain affinities. A new specimen, Titanomachya gimenezi, shed light on the poorly sampled sauropod fauna from central Patagonia.

The evolution of body mass in this clade is a key element to understand sauropod evolution. Discovered in the late Cretaceous sediments of the La Colonia Formation, at Norte de Cerro Bayo in Chubut Province of Patagonia, Argentina, Titanomachya gimenezi is a small bodied saltasauroid, and the first to be recognised from Central Patagonia for the end-Cretaceous.

Titanomachya gimenezi, holotype. MPEF Pv 11547/1, right femur in A, anterior; B, proximal; C, medial; D, posterior and E, distal views. Scale bar = 20 cm. From Pérez-Moreno et al, 2024.

 

The holotype (MPEF Pv 11547) is a partial skeleton including a posterior caudal vertebra, several incomplete ribs, the left humerus, fragments of the pelvic girdle, part of both femora, and parts of both astragali. Body mass estimated suggests that Titanomachya gimenezi  weighted 5.79 to 9.79 tons.

The generic name is derived from the battle in which the Olympians defeat the Titans in ancient Greek mythology. The specific name, honours the late Dr. Olga Giménez, the first female palaeontologist that studied the dinosaurs from Chubut Province.

Among the unique combination of features exhibits by Titanomachya are: a prominent development of the humeral deltopectoral attachment, a straight or slightly curved humeral lateral margin, extremely reduced cnemial crests on the tibiae, a symmetrical development of the articular surfaces on the astragalus and a strong posterior bulge on the astragalus.

References:

Pérez-Moreno, A., Salgado, L., Carballido, J. L., Otero, A., & Pol, D. (2024). A new titanosaur from the La Colonia Formation (Campanian-Maastrichtian), Chubut Province, Argentina. Historical Biology, 1–20. https://doi.org/10.1080/08912963.2024.2332997

Mazzetta, G. V., Christiansen, P., & Fariña, R. a. (2004). Giants and Bizarres: Body Size of Some Southern South American Cretaceous Dinosaurs. Historical Biology: A Journal of Paleobiology, 16(2–4), 71–83. http://dx.doi.org/10.1080/08912960410001715132

 

On the bicentenary of Mary Anning’s Plesiosaurus.

Plesiosaurus dolichodeirus found by Mary Anning. From: W D Conybeare, 1824

Mary Anning was born on Lyme Regis on May 21, 1799. Her father was a carpenter and an amateur fossil collector who died when Mary was eleven. He trained Mary and her brother Joseph in how to look and clean fossils. After the death of her father, Mary and Joseph used those skills to search fossils on the local cliffs, that sold as “curiosities”. The source of the fossils was the coastal cliffs around Lyme Regis, one of the richest fossil locations in England and part of a geological formation known as the Blue Lias.

On December 10, 1823, Mary Anning discovered the first complete Plesiosaur skeleton at the same cliff where she found the Ichthyosaur. The new creature had a tiny head and a remarkable long neck. She sent a number of letters addressed to Sir Henry Bunbury, a member of the Geological Society, and to William Buckland, provinding a sketch and a detailed description of the three metre by two metre wide specimen.

In one of the letters to Bunbury she wrote: “Sir. I have endeavoured in a rough sketch to give you some idea of what it is like. Sir you understand me right in thinking that I said it was the supposed plesiosaurus [sic], but its remarkable long neck and small head, shows that it does not in the least verifie [sic] their conjecturs [sic]; in its Analogy to the Ichthyasaurus, it is large and heavy but one thing I may venture to assure you it is the first and only one discovered in Europe, Colonel Birch offered one hundred guineas for it unseen, but your letter came one day past before [but] I consider your claim to be an answer prior to this, Should you like it the price I ask for it is one hundred and ten pounds, one hundred guineas was my intended price, but if take the same sum as Col B offered he would think I had used him ill in not taking his money.”

Mary Anning´s letter to H. Bunbury from December 19, 1823, about the discovery of a plesiosaur. From the Wellcome Collection..

These letters reveals the scientific networks where Mary Anning was involved in as a fossil dealer. Buckland, for its part, informed about the discovery to Richard Grenville, first Duke of Buckingham, who later purchased the fossil for 150 guineas.

William Conybeare, also heard about the specimen and hurried to Lyme Regis to see it in situ. In 1821, Conybeare and Henry de la Beche, described a partial skeleton discovered in the collection of Colonel Thomas James Birch, and named it Plesiosaurus (from the Greek word plèsios, “closer to”, and the Latin word saurus, “lizard”) meaning that the strange creature was more like a  reptile. The new specimen acquired by the Duke of Buckingham was transported to the Geological Society for its meeting of  20 February 1824.

A sketch of a Plesiosaur by Mary Anning, 1824. From original manuscripts held at the Natural History Museum, London. © The Natural History Museum, London

Conybeare’s original account began as follows:  “I AM highly gratified in being– able to lay before the Society an account of an almost perfect skeleton of Plesiosaurus, a new fossil genus, which, from the consideration of several fragments found only in a disjointed state, I felt myself authorized to propound in the year 1821, and which I described in the Geological Transactions for that and the following year. It is through the kind liberality of its possessor, the Duke of Buckingham, that this specimen has been placed for a time at the disposal of my friend Professor Buckland for the purpose of scientific investigation.”

Mary Anning not only discovered the skeleton, but she prepared the fossil and even made the sketch that Conybeare used in his presentation to the Geological Society. But Conybeare never mentioned Mary Anning in his work.

The plesiosaur purchased from Mary Anning by Constant Prevost.

Noticed about the oddity of the specimen, George Cuvier wrote to William Conybeare suggesting that the find was a fake produced by combining fossil bones from different animals. The unexpected proportions of the neck, raised the suspicions of Cuvier. But William Buckland and Conybeare sent a letter to Cuvier including anatomical details, an engraving of the specimen and a sketch made by Mary Morland (Buckland’s wife) based on Mary Anning’s own drawings and they convinced Cuvier that this specimen was a genuine find. From that moment, Cuvier treated Mary Anning as a legitimate and respectable fossil collector and unlike Conybeare, Cuvier cited her name in his publications.

In May 1824, Cuvier sent geologist Constant Prévost to England for an official geological trip, supported by the administration of the Palaeontology Gallery of the Muséum National d’Histoire Naturelle. In June 1824 Prévost – accompanied by Charles Lyell-   went to Lyme Regis and met Mary Anning. He bought a plesiosaur for £10 and sent it to Paris. Cuvier included the  engraving of his plesiosaur in a third edition of his “Discours sur les révolutions de la surface du globe”. 

References:

Conybeare, William (1824), “On the Discovery of an almost perfect Skeleton of the Plesiosaurus”, Transactions of the Geological Society of London, Geological Society of London, S2-1 (2): 381–389, doi:10.1144/transgslb.1.2.381, S2CID 129024288

MacFarlane, R. (2023). Mary Anning (1799–1847): Letters from Anning to Sir Henry Bunbury (1823). In H. Wills, S. Harrison, E. Jones, F. Lawrence-Mackey, & R. Martin (Eds.), Women in the History of Science: A sourcebook (pp. 261–265). UCL Press. https://doi.org/10.2307/j.ctv2w61bc7.47.

 

Vincent, P., Taquet, P., Fischer, V., Bardet, N., Falconnet, J., & Godefroit, P. (2014). Mary Anning’s legacy to French vertebrate palaeontology. Geological Magazine, 151(1), 7-20.

 

Davis, Larry E. (2012) “Mary Anning: Princess of Palaeontology and Geological Lioness,”The Compass: Earth Science Journal of Sigma Gamma Epsilon: Vol. 84: Iss. 1, Article 8.

200 years of the great Fossil Lizard of Stonesfield

 

Megalosaurus’ jaw and teeth drawn by Mary Buckland. From Buckland, 1824.

On 20 February 1824, William Buckland read at a meeting of the Geological Society of London, the first scientific report of a large carnivore animal, the Megalosaurus: “I AM induced to lay before the Geological Society the annexed representations of parts of the skeleton of an enormous fossil animal, found at Stonesfield near Woodstock, about twelve miles to the north-west of Oxford… The detached bones here represented must have belonged to several individuals of various ages and sizes; there are others in the Oxford Museum which are derived from a very young animal; in the same stratum with them there occur also fragments of large bones, of similar structure, which have been rolled to the state of pebbles. Although the known parts of the skeleton are at present very limited, they are yet sufficient to determine the place of the animal in the zoological system. Whilst the vertebral column and extremities much resemble those of quadrupeds, the teeth show the creature to have been oviparous, and to have belonged to the order of Saurians, or Lizards” (Buckland 1824: 390).

Buckland was in the possesion of a piece of a lower jaw, some vertebrae, and fragments of a pelvis, a scapula and hind limbs, probably not all from the same individual. Buckland’s published description was based on specimens in the Ashmolean Museum, in the collection of Gideon Algernon Mantell of Lewes in Sussex and a sacrum donated by Henry Warburton (1784–1858).

Plate from Plot’s 1677 book The Natural History of Oxford-shire with his illustration of the lower extremity of the famed femur .

The first finds of large bones from the Stonesfield Quarries were made in the late 17th century. Robert Plot (1640-1696), Oxford’s first Professor of Chemistry and first Keeper of the Ashmolean Museum, described and illustrated a distal fragment of a large femur that he interpreted as the remains of a giant man, like those mentioned in the Bible, or of some other animal,  in his monumental work “A natural history of Oxford-shire.”   The fossil came into Plot’s hands through Sir Thomas Pennyston. In 1763,  Richard Brookes, re-described the fossil and named “Scrotum humanum“, but the label was not considered a proper Linnaean name and was not used in posterior literature. 

But probably the first description of a definite dinosaur bone from Stonesfield was made by James Platt at a meeting of the Royal Society of London on February 2, 1758. The paper was published as “An account of the fossile thigh-bone of a large animal, dug up at Stonesfield, near Woodstock in Oxfordshire, in a letter to Mr. Peter Collinson, F.R.S. from Mr Joshua Platt”. After Platt’s death in 1776 his collection was sold at auction including the original Stonesfield thigh bone. 

Megalosaurus sacrum with fused vertebrae (from Buckland 1824, pl. 42).

Sir Christopher Pegge, Regius Professor of Anatomy, in Oxford, also played a key role in the description and discovery of Megalosaurus. In 1797, he acquired the iconic right dentary of Megalosaurus for the collection  of the Christ Church Anatomy School. Buckland attended Pegge’s lectures in Oxford. Thanks to his connections with Pegge and his friendship with William Conybeare, Buckland knew about  the Stonesfield jaw and Henry Warburton’s sacrum, presented to the Geological Society of London in June 1817. Two other important contributor  to the story were the  famous anatomist George Cuvier, and Mary Morland.

Mary Buckland, from an original photograph in the possession of Mrs. Phyllis Cursham (Wikimedia Commons)

Mary was born in Abingdon, Berkshire in 1797. She was the eldest daughter of the solicitor Benjamin Morland and his wife Harriet Baster. After her mother’s death she spent much of her childhood in the house of Sir Christopher Pegge and his wife. Pegge encouraged Mary’s scientific curiosity.

She later made models of fossils for the Oxford museum and repaired broken fossils. She met Buckland in 1818 and helped him with his geological researches and illustrated some of his work like Reliquiae Diluvianae (1823) and the 1824 Megalosaurus paper. She also illustrated some of George Cuvier’s work. In her correspondence with Cuvier, Mary included drawings of some of the Stonesfield bones.

William Buckland (1784-1856).

In 1818 Cuvier went to England and visited Buckland. After examined the bones. He agreed with Buckland that the Stonesfield bones belonged to a giant reptile. Six years later, Cuvier wrote a letter to thank Mary Morland for her drawings, and Buckland for the fossils from Stonesfield.

William Buckland took up the presidency of the Geological Society in 1824. He and Mary Morland married on December 31, 1825. The same year that Iguanodon entered in the books of History.

Iguanodon battling Megalosaurus by Édouard Riou. From Wikimedia Commons

Megalosaurus became so popular that is mentioned in Charles Dickens’s novel Bleak House: “Implacable November weather. As much mud in the streets as if the waters had but newly retired from the face of the earth, and it would not be wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborn Hill.” It was the first appearance of a dinosaur in popular literature.

References:

Buckland, W. (1824). Notice on the Megalosaurus or great fossil lizard of Stonesfield, Transactions of the Geological Society of London (2) 1: 390-396.

Plot, R., (1677). The natural history of Oxford-shire, being an essay towards the natural history of England, Oxford.

Platt, J., (1758). An account of the fossil thigh-bone of a large animal, dug up at Stonesfield, near Woodstock in Oxfordshire. Philosophical transactions of the Royal Society 50: 524-527.

Howlett, E. A., Kennedy, W. J., Powell, H. P., & Torrens, H. S. (2017).. New light on the history of Megalosaurus, the great lizard of Stonesfield. Archives of natural history, 44(1), 82-102.

Forgotten women of Paleontology: Carol Heubusch Faul

Carol Heubusch Faul (1934-1989). Image credit: Buffalo Museum of Science.

The lack of diversity in Geosciences is a long-standing issue. The  geoscientist is often seen as an athletic, bearded white male, and that stereotype has created an “image problem” that prevents minorities from applying for research opportunities. The  problem is even bigger for people with disabilities. In 1978, during a conference for Science Education for Handicapped Student, Carol Heubusch Faul, a geologist and paleontologist, presented GEOLOGY AS A CAREER FOR THE DISABLE, a resume about the “problems and solutions for the orthopedically disabled geology student and the professional geologist” (1).

Carol Heubusch was born in Buffalo, New York, in 1934. She contracted polio when was a teenager. As a consequence, she had lower-body paralysis. Despite the prejudices, she decided to study geology, and attended at the University of Buffalo. She obteined a master degree and soon later began working at the Buffalo Museum of Science in 1955.

In 1959 she became the museum’s Curator of Geology. The same year she participated in the excavations by the Buffalo Museum of Science at the recent discovered Byron Dig site, and wrote about the findings, that included several teeth and fragmentary mastodon bones.

Carol Heubusch at the Byron Dig/Hiscock site, c. 1959. Image credit: Buffalo Museum of Science.

In 1962, after departed the museum, she became the only woman elected to the Council of the Geological Society of America. Four years later she married with Henry Faul, and joined her husband, at the Department of Geology in the University of Pennsylvania. Henry Faul (1920–1981) was a prominent geologist who worked on Enrico Fermi’s team at the University of Chicago, and later participated in the Manhattan Project. 

In 1974, Carol and her husband taught in Shiraz, Iran, and collected Permian fossils. They later wrote a book: It began with a stone: A history of geology from the Stone Age to the age of plate tectonics. The book was published in 1983, after Henry’s death and completed by Carol. In the preface, she wrote: “Readers will note that there is a paucity of women mentioned in this history of the Earth sciences. I wish to acknowledge the contributions of the multitude of anonymous women who were surely there influencing the ‘founders’ of geology.”

Carol Heubusch Faul also wrote A history of geology at the University of Pennsylvania: Benjamin Franklin and the rest (1985), and coauthored two more books (Explorations in Doughty’s Arabia Deserta, and A history of geology and geological education in China).  She died in 1989.

References:

Faul, C. 1978. Geology as a career for the disabled. Pp. 150–153 in H. Hofman, ed. A Working Conference on Science Education for Handicapped Students: Proceedings (April 3–5, 1978). ERIC (1)

Faul, H., and C. Faul. 1983. It began with a stone: A history of geology from the Stone Age to the age of plate tectonics. J. Wiley, New York.

Dutt, K. Race and racism in the geosciences. Nat. Geosci. 13, 2–3 (2020). https://doi.org/10.1038/s41561-019-0519-z

 

Introducing Sidersaura

Sidersaura marae. Image credit: Gabriel Diaz Yantén

Rebbachisauridae is a family of  small to mid-sized sauropod dinosaurs characterized by their highly modified skulls and cervical and dorsal vertebrae with single neural spines. This clade of basal diplodocoid sauropods are known from the early Late Cretaceous of Africa, South America, and Europe. They were part of the sauropod faunas of Argentina together with macronarians (Titanosauriformes) and other diplodocoids (Dicraeosauridae). It was not until 1990 that sauropod specialist John McIntosh realized that a vertebrba described by Franz Nopcsa in 1902, proceeding from the Upper Cretaceous of Neuquen, was anatomically similar to the African Rebbachisaurus garasbae. Later, Bonaparte described Rayososaurus agrioensis, from the Candeleros Formation,  Neuquén province, Argentina, and noted some similarities with R. garasbae, and he proposed Rebbachisauridae as a new sauropod clade.

Sidersaura marae, a new specimen from the Huincul Formation (upper Cenomanian – Turonian) of Neuquén Province, Argentina adds new light about the evolutionary history of rebbachisauridae. The holotype (MMCh-Pv 70) includes a partial skull, partial dorsal vertebrae, fourteen caudal vertebrae, five haemal arches, a partial left scapula, pubic peduncle, both tibiae, both distal fibulae, some metatarsals, phalanges, and ungual phalanges. Additional partial specimens were collected from the basal levels of the Huincul Formation.  The generic name derived from the Latin word “sider” (star),  referring to the peculiar shape of some bones located in the tail, called hemal arches, and the Greek word “saura”, the feminine declination of the word “sauros”, meaning “lizard. The specific name honors Mara Ripoll, director of the “Ernesto Bachmann” Paleontological Museum in recognition of her extensive career in that institution.

Sidersaura marae gen. et sp. nov. anterior to middle haemal arch in anterior view (A); anterior to middle haemal arch in anterior &  lateral view (B); middle to posterior haemal arches in anterior &  lateral views (C, D). Scale bars: 5 cm. From Lerzo et al., 2024.

Originally discovered in 2012, Sidersaura had dimensions similar to those of the great Diplodocus, reaching an an estimated mass of 15 ton, and 20 m in length. The most distinctive features of Sidersaura are the presence of a frontoparietal foramen (hole in the cranial roof), a trait shared with dicraeosaurids more derived than Kaatedocus, and a particularly hard skull bones. Another striking feature is the presence of a new tarsal condition with a novel calcaneum morphology more resembling to early branching sauropods than to neosauropods.

References:

Lerzo, L. N.; Gallina, P. A.; Canale, J. I.; Otero, A.; Carballido, J. L.; Apesteguía, S. y Makovicky, P. J. (2024). The last of the oldies: a basal rebbachisaurid (Sauropoda, Diplodocoidea) from the early. Late Cretaceous (Cenomanian–Turonian) of Patagonia, Argentina, Historical Biology, DOI: 10.1080/08912963.2023.2297914 

Salgado, Leonardo; Gallina, Pablo Ariel; Lerzo, Lucas Nicolas; Canudo, Jose Ignacio; Highly Specialized Diplodocoids: The Rebbachisauridae; Springer Nature Switzerland AG; 2022; 165-208

Top Fossil discoveries of 2023

An artistic reconstruction of the passage of the group of sauropods, a small theropod, and an iguanodon. Image credit: Jorge Gonzalez

This year was marked by extreme weather, earthquakes, intense volcanic activity, and political and humanitarian crisis. The end of the year was particulary dramatic for science in Argentina after the winning of the far-right presidencial candidate who is a denier of climate change and has decided to stop funding scientific research. But resilience is a key factor among humans and science is particulary adjusted to persist against all odds.

Here is my list of the top fossil discoveries of 2023.

• The Oldest Ichtyosaur from the Arctic.

Stratigraphic context and morphology of the earliest ichthyopterygian fossils. Image credit: Øyvind Hammer and Jørn Hurum

Ichthyosaurs were iconic marine reptiles that roamed the Mesozoic oceans for some 160 million years. They were characterized by an elongated body, a relatively small head, a long snout, flipper shaped limbs, and dolphin-like tail flukes. A new study from the Uppsala University and the University of Oslo with new ichthyopterygian material recoverd from the Arctic island of Spitsbergen recalibrates the time and origin of this clade.

The fossil remains designated as PMO 245.975 includes 11 articulated vertebral centra, 15 indeterminate bone fragments, limb and/or limb girdle elements. The centra of PMO 245.975 are comparable with vertebrae from ‘middle-sized’ ichthyopterygian skeletons. Aditionally, their internal organization is also entirely cancellous with a dense circumferentially oriented trabecular network (1). Those features indicates fast growth, elevated metabolism and a fully oceanic lifestyle, evidencing that the earliest ichthyopterygian ancestors must have rapidly adapted as oceanic apex predators.

• The Great Dying: a model for the current biodiversity loss.

The Permo-Triassic boundary at Meishan, China (Photo: Shuzhong Shen)

During the last 540 million years five mass extinction events shaped the history of the Earth. The Permian-Triassic mass extinction (PTME) is the most severe biotic crisis in the fossil record, with as much as 95% of the marine animal species and a similarly high proportion of terrestrial plants and animals going extinct . This great crisis occurred 252 million years ago (Ma), and is linked to the emplacement of the large igneous province of the Siberian Traps.

An international team of researchers from the California Academy of Sciences, the China University of Geosciences (Wuhan), and the University of Bristol, examined fossils from South China (a shallow sea during the Permian-Triassic transition) and recreated the ancient marine environment using simulated food webs to represent the ecosystem before, during, and after the PTME (2). The new study indicates that in the first phase of the extinction community stability slightly decreased despite the loss of more than half of taxonomic diversity, while community stability significantly decreased in the second phase (about 60,000 years after the first biodiversity crissis) because ecosystems are more resistant to environmental change when there are multiple species that perform similar functions. Once the last species in each role began to go extinct, the ecosystem rapidly collapsed.

• Dinosaurs vs mammals.

Psittacosaurus lujiatunensis–Repenomamus robustus pair (WZSSM VF000011). Scale bar equals 10 cm. From Han et al., 2023.

Dinosaurs and mammals have coexisted since the Late Triassic period. However, direct fossil evidence for their interaction is rare. A remarkable fossil (WZSSM VF000011) from the Lujiatun Member of the Lower Cretaceous Yixian Formation in China, reveals an old battle between a cat-sized mammal (Repenomamus robustus, a triconodont mammal) and a dinosaur (Psittacosaurus lujiatunensis).

Repenomamus robustus and R. giganticus are the largest known Mesozoic mammals. In 2005 a study reveled the presence of the tiny bones of a juvenile Psittacosaurus in the the stomach of a specimen of R. robustus. However, the new fossil shows a Psittacosaurus that is at least three times larger than the R. robustus. The position of the mammal atop the dinosaur, and the grasping and biting actions of the mammal, indicates that the mammal was preying on the dinosaur when the two were entombed by a volcanic debris flow (3).

• A 150-million-year-old ‘dinosaur daycare’.

Map of the tracks. Arrows indicate direction of movement of the sauropod producers. Photo credit: Sebastián Apesteguía.

Bolivia yields an outstanding dinosaur ichnological record. Different ichnosites in the Chuquisaca Department, and the Potosí Department, reveal an outstanding abundance and diversity of theropod, sauropod, ankylosaur and ornithopod footprints. A new ichnosite bearing about 350 dinosaur footprints, discovered by Dr. Gustavo Méndez Torrez, along the shore of the Santa Ana River, near the town of Entre Ríos, in the Department of Tarija, offers a glimpse into a Jurassic kindergarten. More important, with this new discovery Bolivia has dinosaur footprints from the entire Mesozoic Era (4). 

The best preserved trackway exhibits large pedes of about 95 cm and 75 cm in in diameter, sub-ovoidal to roughly sub-rectangular in outline, with three or four claw impressions, and sub-circular manus tracks with two or three digit impressions. The team was able to calculated that the animal’s hips were 3.8 meters above the ground, with a estimated length from nose to tail of 20 meters. Associated with those tracks, the researchers found a large number of small footprints, between 15 cm and 30 cm in diameter. The distribution of these trackways may represent an ichnological example of herd behavior from the Late Jurassic period.

• Venetoraptor gassenae

Skeletal anatomy of V. gassenae gen. et sp. nov. (CAPPA/UFSM 0356). From Müller et al., 2023.

Venetoraptor gassenae, a new lagerpetid species that lived about 230 million years ago in Brazil, was about 1 meter long and weighed between 4 to 8 kilograms. The holotype (CAPPA/UFSM 0356), a partial skeleton of a single individual, including cranial and postcranial elements, was recovered from the reddish mudstones of the Buriol site, Rio Grande do Sul State, Brazil. The most striking features of Venetoraptor are the presence of a toothless beak and enlarged hands with scimitar-like claws. The generic name combines the word raptor, plunderer (Latin) in reference to its raptorial beak and grasping hands and the word Veneto in reference to ‘Vale Vêneto’, a touristic locality in Rio Grande do Sul, Brazil. The specific name honours Mrs Valserina Maria Bulegon Gassen, one of the main people responsible for the foundation of CAPPA/UFSM (5).

An international team led by Rodrigo Muller (from CAPPA/UFSM), and Martin Ezcurra (from CONICET, Argentina), published the discovery on Nature. The new study (that includes the most comprehensive dataset of Triassic Pan-Aves known to date) also found that the body plan of pterosaurs and dinosaurs evolved as part of a broader morphological diversification of ornithodirans during the Late Triassic.

• Chucarosaurus diripienda.

Chucarosaurus diripienda. Image credit: Sebastián Rozadilla.

The Argentinean record of titanosaurs is particularly abundant. The study of this diverse group of sauropod dinosaurs embrace an extensive list of important contributions, which started with Richard Lydekker’s pioneering work on Patagonian dinosaurs. Some of them, were the largest animals to ever walk the Earth: Argentinosaurus, Futalognkosaurus, and Puertasaurus surpassed lengths of 37 m and masses of 70 tons.  The best preserved skeletal elements in South American sauropodomorphs are axial and appendicular one, because distinct factors have limited the preservation of complete and articulated skeletons when the specimens are more than 10 m long.

Discovered in the Upper Cretaceous strata of the Huincul Formation, Chucarosaurus diripienda is the biggest dinosaur found in Rio Negro province. Chucarosaurus lived about 90 million years ago. The body length estimated is ∼ 30 m (98 ft) long. Body mass estimated suggests that Chucarosaurus weighted 40-50 tons. The holotype (MPCA PV 820) includes a complete left humerus, left radius, left complete metacarpal II, left ischium, left femur, left fibular shaft, proximal of right tibia. and distal end of indeterminate metapodial. The femur was roughly 1.9 metres (6.2 ft) long. The humerus is slightly twisted and relatively slender (6).

• A matter of size.

Patagotitan, skeleton cast on display at the Field Museum of Natural History, Chicago, IL. From Wikimedia Commons.

Size is an important matter to both general audiences and scientists interested in dinosaur paleontology. Dinosaurs captived our imagination as masive and fierce creatures that once roamed the Earth. Sauropod dinosaurs were the largest terrestrial vertebrates to ever walk the Earth. Their morphology is easy recognizable: a long, slender neck, a relatively small head, and a tail at the end of a large body supported by four columnar limbs. They evolved from small, gracile, bipedal forms, and it was long thought that acquisition of giant body size in this clade occurred during the Jurassic and was linked to several skeletal modifications. True sauropods only evolved in the Early Jurassic. Ingentia prima, from the Late Triassic of Argentina, weighed up to 11 tons and measured up to 32 feet (10 meters) long, was about three times the size of largest Triassic dinosaurs and similar to the size of Jurassic forms.

A new study by Michael Daniel D’Emic looked across a large dataset of sauropods dinosaurs found evidence that this group evolved superlative size at least three dozen times over the course of a hundred million years, on at least six landmasses and in five ecomorphologically disparate clades (7)

• Lips don’t lie.

Close up of “Sue” at the Field Museum of Natural History in Chicago, IL (From Wikipedia Commons)

The iconic Tyrannosaurus rex have been portrayed as a ferocious creature possessing jaws full of exposed teeth and no lips. The reason for this depiction relays in the enormous size of their teeth and their phylogenetic association to crocodylians. A new study lead by Thomas Cullen, Professor of Paleobiology at Auburn University, defies the common perceptions about the appearance of these iconic predators (8).

Based on the pattern of the enamel of dinosaur teeth and crocodiles, dental histology and morphological comparisons, the researchers suggest that  lips would have protected the teeth and helped keep them from drying out due to the exposure from the elements.

• The sea monster from the End of the World.

Rearticulated skull and jaw of NDGS 10838 in left lateral view, with left bones labeled. From Zietlow et al., 2023.

Mosasaurs were large carnivorous aquatic lizards with a global distribution that lived during the Cretaceous Period. Their first fossil remains were discovered in a chalk quarry near Maastricht, in the Netherlands, and were initially identified as a whale. A few decades later, Georges Cuvier, the ‘Father of Paleontology’, confirmed the animal’s identity as some kind of gigantic extinct lizard, with some similarities in the morphology of the bones to those of contemporary monitor lizard. Jormungandr walhallaensis (named after the Norse sea serpent), from the Pembina Member of the Pierre Shale Formation in Cavalier County, North Dakota, is a new genus and species of mosasaurine mosasaur.

Discovered in 2015, the holotype (NDGS 10838) comprises a partial skull, seven cervical vertebrae with three hypapophyseal peduncles, 11 ribs, and five anterior dorsal vertebrae.  Jormungandr walhallaensis is estimated to be about 7 meters (24 feet) long, and lived about 80 million years ago. The new taxon shares some features with Plotosaurini (a sister genus to Mosasaurus) and Clidastes (a smaller and more primitive form of mosasaur, part of the Mosasaurinae subfamily) suggesting it may represent a transitional form between the two (9).

• The last meal.

Stomach contents of Gorgosaurus. From Therrien et al., 2023.

Discoverd in 2009 at the Dinosaur Provincial Park, east of the Canadian city of Calgary, the skeleton of a young Gorgosaurus libratus, a tyrannosaurid theropod dinosaur that lived during the Late Cretaceous Period, preserves the articulated hindlimbs of two yearling Citipes, a genus of caenagnathid dinosaurs, inside its abdominal cavity. The fossil, described by a team lead by Francois Therrien of the Royal Tyrrell Museum, provides direct fossil evidence of diet and feeding behavior in young tyrannosaurids (10).

The new study suggests that tyrannosaurids underwent a major ecological and dietary shift over the course of their life span. Previos studies indcate that tyrannosaurids are united by a conservative pattern of growth in which the skulls of juveniles were entirely reshaped during ontogeny: the skull and the jaws deepened, pneumatic bones inflated, the ornamented structures enlarged and coarsened, the sutural surfaces deepened and became more rugose, and the teeth became larger and thicker. In the post-cranial skeleton the most notably change is the shortned of the forearm.

Reference:

Kear, B. P., Engelschiøn, V. S., Hammer, Ø., Roberts, A. J., & Hurum, J. H. (2023). Earliest Triassic ichthyosaur fossils push back oceanic reptile origins. Current Biology: CB, 33(5), R178–R179. https://doi.org/10.1016/j.cub.2022.12.053 (1)

Huang, Y., Chen, Z. Q., Roopnarine, P. D., Benton, M. J., Zhao, L., Feng, X., & Li, Z. (2023). The stability and collapse of marine ecosystems during the Permian-Triassic mass extinction. Current Biology. DOI: 10.1016/j.cub.2023.02.007 (2)

Han, G., Mallon, J.C., Lussier, A.J. et al. An extraordinary fossil captures the struggle for existence during the Mesozoic. Sci Rep 13, 11221 (2023). https://doi.org/10.1038/s41598-023-37545-8 (3)

Méndez Torrez, G., Lovera Cruz, L., Céspedes-Llave, A. Á., Esperante, R., Gutiérrez Berrios, C., & Apesteguía, S. (2023). First Jurassic to earliest Cretaceous dinosaur footprints for Bolivia at the Castellón formation (Tacurú Group), Tarija. Historical Biology, 1-20. https://doi.org/10.1080/08912963.2023.2235373 (4)

Müller, R.T., Ezcurra, M.D., Garcia, M.S. et al. New reptile shows dinosaurs and pterosaurs evolved among diverse precursors. Nature 620, 589–594 (2023). https://doi.org/10.1038/s41586-023-06359-z (5)

F.L. Agnolin et al. A new gigant titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous of Northwestern Patagonia, Argentina. Cretaceous Research, published online February 2, 2023; doi: 10.1016/j.cretres.2023.105487 (6)

D’Emic MD. The evolution of maximum terrestrial body mass in sauropod dinosaurs. Curr Biol. 2023 May 8;33(9):R349-R350. doi: 10.1016/j.cub.2023.02.067 (7)

Cullen, Thomas M. et al, Theropod dinosaur facial reconstruction and the importance of soft tissues in paleobiology, Science (2023). DOI: 10.1126/science.abo7877. (8)

Zietlow, Amelia R. et al, Jormungandr walhallaensis: a new mosasaurine (Squamata: Mosasauroidea) from the Pierre Shale Formation (Pembina Member: Middle Campanian) of North Dakota, Bulletin of the American Museum of Natural History (2023). https://digitallibrary.amnh.org/items/13b0485f-c73f-47f9-8d1d-0d4ab6aaedfb (9).

François Therrien et al, Exceptionally preserved stomach contents of a young tyrannosaurid reveal an ontogenetic dietary shift in an iconic extinct predator, Science Advances (2023). DOI: 10.1126/sciadv.adi0505 (10)

Victorian Christmas cards

The first Christmas card by artist John Callcott Horsley. From Wikimedia Commons.

The tradition of sending Christmas cards became very popular in the Victorian period (1837-1901). Queen Victoria and her husband, Prince Albert, introduced German holiday traditions to England. But it wasn’t until 1846 that the fir tree became a worldwide custom, after the Queen and her husband were sketched in the Illustrated London News standing with their children around a Christmas tree. Early Christmas cards often contained flowers, fairies and little animals. With the increasing popularity and more affordable costs, people began to ask for a variery of themes including some bizarre, and ghoulish images.

The first commercial Christmas card was commissioned by Sir Henry Cole, who later became the first director of London’s Victoria and Albert Museum, in 1843. It featured a happy family gathered around a table. The same year, A Christmas Carol by Charles Dickens is published. This book revitalized the traditions of Christmas and to Victorian England, Dickens was Christmas.

By the end of 1850s, Darwin published On the Origin of Species and that could influenced some of the designs for such cards as well. Dickens himself contributed to the popularity of geology with the creation of ideas and images for public consumption, such as he did in Bleak House, with the description of the streets of London where ancient lizards roamed, and volcanoes and quakes shocked the Earth.

Among the most notoriuos Christmas card are those printed by Thomas De la Rue for the Natural History Museum of London depicting the more important paleontological discoveries of the time. The most notorious is ‘Ideal impression of a future creation discovered by professors Ichthyosaurus, Megalosaurus and Co.’ One of the possible source of inspiration for this card is a cartoon drawn by Henry De la Beche entitled “Awful Changes. Man Found only in a Fossil State – Reappearance of Ichthyosauri”, that featured an assemblage of reptiles listening to a lecture from an ichthyosaur about the fossil find of an “ancient” human skull. The cartoon was a criticism to Lyell’s uniformitarianism.

“Awful Changes. Man Found only in a Fossil State – Reappearance of Ichthyosauri” (c. 1830) From Wikimedia Commons.

References:

A. BUCKLAND, ‘“The Poetry of Science”: Charles Dickens, Geology and Visual and Material Culture in Victorian London’, Victorian Literature and Culture, 35 (2007), 679–94 (p. 680).

Halloween Special XI: The sea monster from the End of the World.

Thor Battering the Midgard Serpent (c. 1790) by Henry Fuseli. From Wikipedia Commons.

In Norse Mythology, Loki, the god of mischief, and Angrboða, a giant from Jotunneim, gave birth to three fearsome creatures: Fenrir, the giant wolf, Hel, the goddess of the Norse underworld, and Jörmungandr, a sea serpent. When Odin received the prophecy that the creatures will be a menace to the power of the gods, he confined them to different realms.  Jörmungandr was cast to the great ocean that was believed to encircle Midgard, the world of mortals. It was prophesized that Jormungandr would have a bitter rivalry with Thor, the god of thunder. They shall fight three times and their final battle will be at Ragnarok, the twilight of the gods, when Jormungandr will finally leave the oceans and poison the sky.
Jormungandr was first mentioned in stories from around 200 AD, and appears on several pre-Christian and early Christian rune stones and engravings. Creatures like Jormungandr are repetead elements on diferentes cosmogies aroound the world. In South Asian myths, Naga is the god of oceans, responsible for the tides, floods, and waves.

The discovery of the bodies of  huge animals and fossil bones has always stimulated the imagination of local people, giving rise to myths and legends. In 1968, American writer Lyon Sprague de Camp wrote in The Magazine of Fantasy and Science Fiction: “After Mesozoic reptiles became well-known, reports of sea serpents, which until then had tended towards the serpentine, began to describe the monster as more and more resembling a Mesozoic marine reptile like a plesiosaur or a mosasaur.” 

Mosasaurs were large carnivorous aquatic lizards with a global distribution that lived during the Cretaceous Period. Their first fossil remains were discovered in a chalk quarry near Maastricht, in the Netherlands, and were initially identified as a whale. A few decades later, Georges Cuvier, the ‘Father of Paleontology’, confirmed the animal’s identity as some kind of gigantic extinct lizard, with some similarities in the morphology of the bones to those of contemporary monitor lizard.

Rearticulated skull and jaw of NDGS 10838 in left lateral view, with left bones labeled. From Zietlow et al., 2023.

Jormungandr walhallaensis (named after the Norse sea serpent), from the Pembina Member of the Pierre Shale Formation in Cavalier County, North Dakota, is a new genus and species of mosasaurine mosasaur. Discovered in 2015, the holotype (NDGS 10838) comprises a partial skull, seven cervical vertebrae with three hypapophyseal peduncles, 11 ribs, and five anterior dorsal vertebrae. 

Jormungandr walhallaensis is estimated to be about 7 meters (24 feet) long, and lived about 80 million years ago. The new taxon shares some features with Plotosaurini (a sister genus to Mosasaurus) and Clidastes (a smaller and more primitive form of mosasaur, part of the Mosasaurinae subfamily) suggesting it may represent a transitional form between the two.

 

References:

Zietlow, Amelia R. et al, Jormungandr walhallaensis: a new mosasaurine (Squamata: Mosasauroidea) from the Pierre Shale Formation (Pembina Member: Middle Campanian) of North Dakota, Bulletin of the American Museum of Natural History (2023). https://digitallibrary.amnh.org/items/13b0485f-c73f-47f9-8d1d-0d4ab6aaedfb

The first Jurassic dinosaur ichnosite from Bolivia: a 150-million-year-old ‘dinosaur daycare’.

An artistic reconstruction of the passage of the group of sauropods, a small theropod, and an iguanodon. Image credit: Jorge Gonzalez

Bolivia yields an outstanding dinosaur ichnological record. Different ichnosites in the Chuquisaca Department, and the Potosí Department, reveal an outstanding abundance and diversity of theropod, sauropod, ankylosaur and ornithopod footprints. But most of its deposits were restricted to the Triassic period (220 million years old) and to the last moment of the Upper Cretaceous (between 75 and 65 million years ago). A new ichnosite bearing about 350 dinosaur footprints, discovered by Dr. Gustavo Méndez Torrez, along the shore of the Santa Ana River, near the town of Entre Ríos, in the Department of Tarija, offers a glimpse into a Jurassic kindergarten. More important, with this new discovery Bolivia has dinosaur footprints from the entire Mesozoic Era. 

During the Late Jurassic, Gondwana was split into a northern and southern continent by the rift system opening the proto-Indian Ocean. The geological and geochemical record suggest that low-latitude environments were arid and tropical ever-wet conditions were absent. Maximum plant diversity was concentrated at midlatitudes, whith forests dominated by a mixture of conifers, cycadophytes, pteridosperms, ferns, and sphenophytes. The vast Botucatú Desert, which ran from Bolivia to Brazil and had its counterpart in Africa, occupied the center of Gondwana. In this scenario, sauropodomorph diversity patterns reached a peak similar with those of theropods and ornithischians.

Map of the tracks. Arrows indicate direction of movement of the sauropod producers. Photo credit: Sebastián Apesteguía.

The dinosaur traces from Tarija are abundant. They are recorded in 10 different levels, most of them correspond to long-necked sauropod dinosaurs, with  the exception of few tridactyl tracks. The best preserved trackway exhibits large pedes of about 95 cm and 75 cm in in diameter, sub-ovoidal to roughly sub-rectangular in outline, with three or four claw impressions, and sub-circular manus tracks with two or three digit impressions. The team was able to calculated that the animal’s hips were 3.8 meters above the ground, with a estimated length from nose to tail of 20 meters. Associated with those tracks, the researchers found a large number of small footprints, between 15 cm and 30 cm in diameter. The distribution of these trackways may represent an ichnological example of herd behavior from the Late Jurassic period.

 

References:

Méndez Torrez, G., Lovera Cruz, L., Céspedes-Llave, A. Á., Esperante, R., Gutiérrez Berrios, C., & Apesteguía, S. (2023). First Jurassic to earliest Cretaceous dinosaur footprints for Bolivia at the Castellón formation (Tacurú Group), Tarija. Historical Biology, 1-20. https://doi.org/10.1080/08912963.2023.2235373

Introducing Venetoraptor gassenae.

Venetoraptor gassenae. Image credit: Matheus Fernandes

Pterosaurs were the first flying vertebrates. Their reign extended to every continent and achieved high levels of morphologic and taxonomic diversity during the Mesozoic. During their 160 million year history, the evolution of pterosaurs resulted in a variety of eco-morphological adaptations, as evidenced by differences in skull shape, dentition, neck length, tail length and wing span. Due to the fragile nature of their skeletons and the absence of fossils with transitional morphologies, the origin of pterosaurs is one of the most debated topic in vertebrate paleontology. 

Lagerpetids are small to medium-sized (less than 1 m long), cursorial, non-volant reptiles from Middle–Upper Triassic of Argentina, Brazil, Madagascar, and North America. Previous studies of lagerpetid anatomy was mostly limited to vertebrae, hindlimbs and a few cranial bones, but new fossil discoveries over the past few years have greatly increased the understanding of this group. Based on the anatomical information from Lagerpeton chanarensis (from the Chañares formation, Argentina), Ixalerpeton polesinensis (from the Santa Maria Formation, Brazil), Kongonaphon kely (from Morondava Basin, Madagascar), and Dromomeron spp. (from North America), Martin Ezcurra elucidated their relationship to pterosaurs on a study published in 2020.

The recognition of the lagerpetids as the sister taxon to pterosaurs provides clues to study the origin of Pterosauria, its specialized body plan and flying abilities. Venetoraptor gassenae, a new lagerpetid species that lived about 230 million years ago in Brazil, shed new light on the evolution of pterosaurs and their closest relatives, the dinosaurs.

 

Skeletal anatomy of V. gassenae gen. et sp. nov. (CAPPA/UFSM 0356). From Müller et al., 2023.

An international team led by Rodrigo Muller (from CAPPA/UFSM), and Martin Ezcurra (from CONICET, Argentina), published the discovery on Nature. The new study (that includes the most comprehensive dataset of Triassic Pan-Aves known to date) also found that the body plan of pterosaurs and dinosaurs evolved as part of a broader morphological diversification of ornithodirans during the Late Triassic.

Venetoraptor gassenae was about 1 meter long and weighed between 4 to 8 kilograms. The holotype (CAPPA/UFSM 0356), a partial skeleton of a single individual, including cranial and postcranial elements, was recovered from the reddish mudstones of the Buriol site, Rio Grande do Sul State, Brazil. The most striking features of Venetoraptor are the presence of a toothless beak and enlarged hands with scimitar-like claws. The generic name combines the word raptor, plunderer (Latin) in reference to its raptorial beak and grasping hands and the word Veneto in reference to ‘Vale Vêneto’, a touristic locality in Rio Grande do Sul, Brazil. The specific name honours Mrs Valserina Maria Bulegon Gassen, one of the main people responsible for the foundation of CAPPA/UFSM.

Although lagerpetids and silesaurids developed an edentulous and sharp anterior tip of the dentary, Venetoraptor differs from all other early ornithodirans in the presence of a dorsoventrally taller, ornamented beak with possible support of a rhamphotheca. The hands of Venetoraptor were highly specialized and provides clues to the behaviour of this reptile.

 

References:

Müller, R.T., Ezcurra, M.D., Garcia, M.S. et al. New reptile shows dinosaurs and pterosaurs evolved among diverse precursors. Nature 620, 589–594 (2023). https://doi.org/10.1038/s41586-023-06359-z

Foffa, D., Dunne, E.M., Nesbitt, S.J. et al. Scleromochlus and the early evolution of Pterosauromorpha. Nature (2022). https://doi.org/10.1038/s41586-022-05284-x

Ezcurra, M.D., Nesbitt, S.J., Bronzati, M. et al. Enigmatic dinosaur precursors bridge the gap to the origin of Pterosauria. Nature (2020). https://doi.org/10.1038/s41586-020-3011-4

Langer, M. C., Ezcurra, M. D., Bittencourt, J. S. & Novas, F. E. The origin and early evolution of dinosaurs. Biol. Rev. 85, 55–110 (2010).